COMPLETE ^WRITlNG^!r

♦ OP

THOMAS SAY, -

ON THE *

Cont|0l0gj) flf t|f MuM States

•

EDITED BY

W. G. BINNEY,

MEMBER OF THE ACADEMY 'W NATURAl, SCIENCES OF PHitiAOELPEJA, E'l'C.

NEW YORK:
• H. BAILLIERE, 2 90 BROADWAY.

LONDON:— H. BAILLIERE, 219 REGENT STREET.

PARIS : — J. B. BAILLIERE ET FILS, RUE HAUTEFEIUILLE.

MADRID : — C. BAILLT-BAILLIERE, CALLE DEL PRINCIPE.

1858-

hix%^

#

PREFACE BY THE EDITOR.

Much of the coufusion which already exists in the synoaoiny of
American MoUusca, has arisen from the general inaccessibility of
the writings of Thomas Say. Scattered through numerous and
costly works and obscure publications, they have always been ob-
tained with difficulty, and for many years past a large portion of
them have become absolutely unattainable. His species have been
known to most American conchologists rather by tradition than
from a careful study of his excellent descriptions ; a fact readily
accounting for the confusion which is to be found in the more
recent American and European works.

To remedy this evil in the department in which my personal study
has been more particularly devoted, I collected and published, in
1856, all Mr. Say's descriptions of land shells. Having since thee
been requested to add the fluviatile and marine species, I have now
undertaken to do so, hoping thereby to induce a just appreciation
of the labors of our greatest Naturalist, as well as to increase the
facilities of the student of American Conchology.

This volume contains all the writings of Mr. Say on recent Con-
chology, excepting his " Glossary of Conchology," and " List of
Exotic Shells in my Cabinet." The extracts from the uunieroas
original works are given as nearly as possible in chronological order,
the descriptions of terrestrial species being placed collectively at
the commencement. To remedy the inconvenience of not having
the various genera and species more nearly collated, I have added
a complete alphabetical catalogue of all the species described in
Mr. Say's writings, with a reference to the date, volume, page, and
figure of the original publication and of this reprint. To this must,
be referred all questions relating to priority of publication of any
disputed species.

The plates include all the figures ever published by Mr. Say.
Plates 1 to 68, inclusive, have been printed from the original copperb
of the " American Conchology." Plates 69, 70, 71, 72, are fac simi-
les of the plates of Nicholson's Encyclopedia. On plate 70 will
also be found fac similes of the figures of Modiola opifex, from the
Journal of the Academy. Plates 73 and 74 are printed from the

IV.

original copper-plates of Long's Expedition, which have been pur-
chased by Mr. Bailliere. Plate 75 is now for the first time published
from a copper-plate prepared by Mr. Say,

All remarks of my own are distinguished by a difi'erent sized type,
and are followed by the letters " Ed."

A large portion of the original manuscript of Mr. Say, and all the
works containing his conchological writings are deposited in the
noble library of the Academy of Natural Sciences of Philadelphia,
in whose collection are still preserved many of the original speci-
mens from which his descriptions were drawn.

I leave to abler hands the rectification of the nomenclature of
Say's species, demanded alike by priority of publication, the advance-
ment of the science, and the much greater facilities for studying
them enjoyed by the American conchologist at the present day.

W. G. BINNEY

Burlington, N. J., June, 1858.

LIST OF WORKS

CONTAINING THB

CONCHOLOGICAL WRITINGS OF THOMAS SAY.

1. The article " Conchology, " from the 4th vol. of the three American

editions of Nicholson's British Encyclopedia of Arts and Sciences.
Philadelphia, 1816, 1818, 1819.

2. A letter on Ocythoe punctata, in the Philosophical Transactions of the

Royal Society. 1819.

3. Numerous articles in the Journal of the Academy of Natural Sciences

of Philadelphia, viz :
Vol. I. Descriptions of seven species of American Fresh Water and
Land Shells, not noticed in the systems. May, 1817.
The same concluded. June, 1817.
Descriptions of new species of Land and Fresh Water Shells of the

United States. Oct., 1817.
Account of two new genera, and several new species of Fresh Water

and Land Shells. June, 1818.
Description of a new genus of Fresh Water Bivalve Shells. Decem-
ber, 1818.
Vol. II. Descriptions of Univalve Shells of the United States. Janu-
ary, 1821.
An account of some of the Marine Shells of the United States.

July, 1822.
The same continued. July, 1822.
The same concluded. July, 1822.

Descriptions of some Univalve Terrestrial and Fluviatile Shells of
the United States. Dec. 1822.
Vol. IV. On a new species of Modiola. May, 1825.
Vol. V. Descriptions of some new species of Fresh Water and Land
Shells of the United States. Sept., 1825.
Descriptions of Marine Shells recently discovered on the coast of
the United States. Feb., 1826.

4. The "MoUusca" in the Appendix to Vol. II. of Major Long's Second

Expedition to the source of St. Peter's River, &c. &c. Phila-
delphia, 1824.

3 The New Harmony Disseminator of Useful Knowledge. New Har-
mony, Indiana.
In octavo, —
Descriptions of some new Terrestrial and Fluviatile Shells of North

America. July 29, 1829.
The same continued, Aug. 12, 1829 ; Ang. 26, 1829 ; Sept. 9, 1829 :
Sept. 23, 1829 ; Oct. 7, 1829 ; Oct. 21, 1829 ; Nov. 4, 1829 ;
Not. 18, 1829.
tn newspaper form, —
The same continued, Dec. 30, 1830 ; Jan. 15, 1831 ; .Ian. 29, 1831.
t>. Transylvanian Journal of Medicine, Lexington, Kentucky.

Descriptions of several new species of Shells, and of a new species
of Lumhricus. Vol. IV., 1831.
'7. American Couchology, New Harmony, Indiana. Part 1^ 1830 ; part
2, Aprit, 1831 ; part 3, September, 1831 ; part 4, March, 1832 ;
part .5, August, 1832 ; part 6, April, 1834 ; part 7, published after
Say's death ; edited by T. A. Conrad.
H. All attempt to exMbit a Synonomy of the Western North American
species of the genera Unio and Alasmodonta, given with part 6
of American Conchology. April, 1334.
Some of the descriptions contained in the New Harmony Dissemina-
tor, not repeated in the American Conchology, were reprinted in
pamphlet form by Mrs. Say, New Harmony, Indiana, 1840.

The American Conchology was intended to contain descriptions and
Jigures of all the known species of American Mollusca. The noble under-
taking was arrested, by the death of the author, at part 6. The sev-
enth number was sufficiently advanced to allow its completion and pub-
lication by Mr. T. A. Conrad. A French translation of parts 1 to 5 has
been published by M. Chern in his Bibliotheque Conchyliologique, vol.
ill.

NoTK. — I have iJersonally consulted all the works referred to above,
vrith the exception of the first American edition of Nicholson's Ency-
nyolopedia. This I have not been able to find. [ give its date as 1816,
>.n the authority of Ferussac, Mag. de Zool. 1835, cl. v. 59, 60, p. 11. I
believe its species to be the same as in the second edition. The dates
in the text and index are invariably of the puhlication of the various
papers, without reference to the time they were read ])efore any Society.
1 u tlie Journal of the Academy, I have been forced to adopt the date
)f the general title page of each volume, unless with the signatures, or
■».t the conxmencement of the various parts, some other date is given.

Being engaged in preparing a continuation of the
work of my father, the late Dr. Amos Binney, on
the " Terrestrial Mollusks and Shells of the United
States," I take this opportunity of soliciting the
assistance of those interested in the subject. Suites
of local species from every part of the Union will
be of great value to me in ascertaining the geogra-
phical distribution of species. They will be grate-
fully acknowledged, and, if required, shells given in
exchange. I would also request any information
relating to the subject, and any addenda or corri-
genda to the "Mollusks,"

Shells may be forwarded safely by mail, if packed
in a pasteboard box, with tissue paper or cotton.
Parcels exceeding the required weight of the Post-
Office, may be sent by express.

W. G. BINNEY.

Address, Acad, of Natural Sciences, Philadelphia.

DERCRIPTIODSrS

TERKESTRIAL SHELLS

NORTH AMERICA

g Cijomas ^ag.

PHILADELPHIA:

C H I L D S & PETERSON,

124, ARCH STREET.

1855.

PREFACE.

Anticipating that the publication of the Plates
forming the third volume of my late father's work
on the " Terrestrial Mollusks and Shells of the
United States," will excite increased attention to
that subject, it has been suggested to me by my
friend, Mr. Thomas Bland of New York, that a re-
print of the original descriptions and accompanjdng
remarks of Thomas Say will materially assist in the
study of this branch of Zoology.

I have accordingly collected and now publish,
from the scattered and generally inaccessible wri-
tings of Mr. Say, all that relates to our terrestrial
species.

These pages are offered to the Conchologists of
America and Europe to aid and encourage them in
their investigations, and to induce a just appreci-
ation of the labors of our first and greatest Naturalist,

W. G. BINNEY.

Germantowri, near Philoddphia,
Nov. 1856.

The Extracts have been made from the following

works :

1. The article Conehology, in the American edition of Nichol-
son's Encyclopsedia, 2d ed. Philad. 1818, vol. iv., with figures.

2. Numerous articles in the Journal of the Academy of Natu-
ral Sciences of Philadelphia, vols. i. ii. v.

3. Expedition to the Source of St. Peter's River, &c. &c., under
the command of Major Long. Vol. ii., Appendix, with figures.
Philad. 1824.

4. American Conehology, or Descriptions of the Shells of North
America. Illustrated by colored figures. New Harmony, Indiana,
1830-34.

5. Disseminator of Useful Knowledge. New Harmony, Indiana,
1829-31.

6. Transylvania Journal of Medicine. Vol. ii., 1882.

The extracts from the last two Journals have been made from
the republication by Mrs. Sat, New Harmony, 1840, under the
title, " Descriptions of some new Terrestrial and Fluviatile Shells
of North America."

DESCRIPTIONS OF

TERRESTRIAL SHELLS OF NORTH AMERICA.

No. 1.— The Article « CONCHOLOGY," in Nicholson's Ency-
clopaedia, Am. Ed., anno 1818.

1. Helix albolabris. — Shell thin, fragile ; convex, imperfo-
rated ; with six volutions, whorls obtusely wrinkled across, and
spirally striated with very fine impressed lines, a little waved by
passing over the wrinkles, both becoming extinct towards the
apex, which is perfectly smooth ; aperture lunated, not angulated
at the base of the column, but obtusely curved, lip contracting the
mouth abruptly, widely reflected, flat and white.

Length of the column three-fifths of an inch ; breadth one inch.

Plate 1, Fig. 1. Lister, Conch, tab. 47. ?•— Rhodia, Gmelin's
Ed. Syst. Nat.

The common garden snail, frequenting moist shaded situations,
and is generally well known. It is very probable that this is the
Rhodia of authors, but as in the description of that species nothing
is mentioned of the reflected lip, and not having in our possession
the volume of Chemn. Conch, referred to for a figure of it, we have
made an interrogative reference, and for the present have adopted
a new name.

2. H. ARBOREUS. — Shell very thin, fragile, depressed, horn
color, pellucid, very little convex : whorls four, irregularly wrinkled
across ; aperture sublunated, lip thin, brittle, junction with the
body whorl acute ; umbilicus large and deep.

Length, one-tenth of an inch nearly; breadth nearly one-fifth.

Plate 4, Fig. 4,

Under the bark of decaying trees very common. Inhabitant
pellucid ; base white, acute behind, not extending forward before
the head ; head and neck dusky ; tentacula four ; lower ones very
short ; eyes placed in the tip of the superior pair.

The application of the Goniometer, upon some commodious con-
struction, might very much facilitate the investigation and deter-
mination of species, by ascertaining the precise angle subtended

by the two sides of the spire in univalves. This angle, combined
■with the length and breadth of the shell, and proportionate length
of the mouth, would, it is conceived, give us a better idea of form
than we can have by the present mode of description. It is a plan
we have adopted in describing our marine shells.

3. H. TRIDENTATA. — Shell depressed, spire very little raised,
brownish or horn color ; whorls five, crossed by numerous raised,
equidistant, acute lines, separated by regular grooves ; aperture
lunate, three toothed ; teeth placed triangularly, one on the pillar
lip situated diagonally ; outer lip abruptly contracting the aper-
ture, widely reflected and white, furnished with two of the teeth
resembling projecting angles. Umbilicus moderate.

Half an inch wide. Inhabits the Middle States. Plate 2, fig. 1.

Cochlea parva, umbilicata, tenuiter striata. Tridens sc. in
triangulo positi, nempe unus ad fundum oris, alter ad columellam,
tertius ad labrum. Lister, Conch, tab. 92, fig. 92.

The three curves formed by the two teeth in the outer lip of
this shell bear considerable resemblance to the ornament often
placed upon panels in Gothic architecture. It is found under the
loose moist bark of decaying trees in some plenty. Belongs to the
genus Polydontes, Montf.

As many of the compound terms as possible ought to be ban-
ished from the language of Natural History, we would therefore
propose that the term ow^er-lip and pillar-li^ be substituted by
Labrum and Labrum; these would be equally expressive, and
occupy less space in a description.

4. H. ALTERNATA. — Shell somewhat convex, fuscous, varied or
alternating with pale rays ; whorls five, striated across with raised
equidistant acute lines, forming grooves between them. Aper-
ture thin and brittle ; lip regularly curved, within glossed with
perlaceous, and when placed before the light, the fuscous lines
appear sanguineous. Umbilicus large, exhibiting all the volutions.

Three-fourths of an inch wide. Inhabits the Mddle States.
Plate 1, fig. 2.

H. radiata, Gmelin's Ed. of Syst. Nat. p. 3634.

Cochlea umbilicata, fusca, sive variegata, capillaribus stryis
leviter exasperata. List. Conch, tab. 70, fig. 69.

Lister's figure, which is, without doubt, a representation of this
species, is referred to in Gmelin as //. Rndiaia, but we believo

our shell to be a distinct species from that which is found iu
France ; we therefore apply a new name. Found under bark of
dead trees and in moist places, and is not uncommon. In the
young shell the whorls are less rounded and flattened above, so as
to form almost an angle with the exterior margin ; the colors arc
altogether paler, and may be described as pale yellow spotted or
above radiate with reddish brown, and a row of spots interrupted
from the radii by the immaculate prominent margin.

5. H. GLAPHYRA. — Shell very much depressed, thin, fragile,
pellucid, polished 5 whorls five, regularly rounded, and with obso-
lete and irregular wrinkles across them ; beneath whitish ; umbi-
licus moderate, not exhibiting the volutions. PI. 1, Fig. 3.
Taken by Mr. Gr. Ord in his garden in Philadelphia.
This species and the preceding are referable to the genus Zoni-
tis, Montf. — a name which- is objectionable from its being used in
Entomology.

It considerably resembles Helix niiens of Europe, particularly
in being whitish beneath, and will be properly arranged next that
species in the systems.

The following species of Helix and other genera were also de-
scribed in this paper, but the descriptions and remarks are merely
a repetition from the Journal of the Academy, vol. i.

Helix thyroidus. Polygyra auriculata.

" minuta. " avara.

" labyrinthica. " septemvolva.

" hirsuta. Oligyra orbiculata.

" perspectiva. Succinea campestris.

" lineata. " ovalis.

Polyphemus glans.

Pupa corticaria. — Shell dextral, cylindrical, obtuse at the
apex : whorls five, not precipitately wrinkled or striate ; aperture
suborbicular, lip reflected ; a single tooth on the pillar lip, near
the outer angle ; inner angle with an angular projection resembling
a second tooth, sometimes obsolete.

Length about the tenth of an inch.

Plate 4, fig. 5. — A, natural size ; C, an enlarged view.

Yery common under the bark of trees, near the earth, and re-
sembles Turbe rmiscorum of authors.

No, 2. — Journal of Academy of Natural Sciences, vol. i., p. 15
et seqq. anno May 1817.

SucciNEA OVALIS. — Shell suboval, pale yellowish, diaphanous,
very thin and fragile, with nearly three oblique volutions. Body
very large ; spire small, but little prominent, somewhat obtuse.
Aperture longitudinally subovate, large. Columella much nar-
rowed, so as almost to permit the view of the interior apex, from
the base of the shell. Scarcely any calcareous deposit on the pillar
lip. Length nine-twentieths of an inch, aperture seven-twentieths.

Inhabits marshy grounds in shaded situations j common. Col-
lection of the Academy.

Animal longer than its shell, furnished with four tentacula, the
two superior ones longer, cylindrical, supporting the eyes ; inferior
ones short, conic. Color pale, with minute black points, which
are assembled into fascia on the sides and fillets on the neck above ;
neck granulate above, a black line passes each side on the neck,
from the tip of the oculiferous tentacula, gradually disappearing
under the shell. Front truncate, quadrate.

When the animal is living, so vitreous is the shell that all the
markings of its body are plainly discernible ; so that although the
shell is of a straw color, immaculate, it appears of a dusky hue,
with a remarkable white, flexuous, longitudinal vitta on the back,
arising from the suture and terminated about midway to the base,
often with two or three obsolete white spots near its tip. The
characters of the inhabitant are widely distinct from the animal of
the Lymngea, and are somewhat allied to those of the inhabitants
of the Helices ; it cannot, however, be referred to Helix with
propriety, as will be evident from the specific description. I have
for the present considered it as of Draparnaud's genus Succinea,
though it somewhat resembles a Bulimus, particularly in its habi-
tat, being a terrestrial species, and in this respect it difi'ers from
Succinea. It may perhaps belong to Lamark's genus Amphibu-
limus.

Helix hirsuta. — Shell subglobose, brownish, imperforated,
covered with short, numerous, rigid hairs ; whorls five, but little
rounded ; suture distinct ; aperture very narrow, almost closed by
an elongated lamelliform tooth, situated on the pillar lip, and cir-

cularly joined to the outer lip at the base. Outer lip reflected
back upon the whorl, and incorporated with it near the base, with
a deep sinus in the middle. Beneath, one quarter of an inch.
Lister, Tab. 93, f. 94 ?

Inhabits moist places ; common. In the collection of the Aca-
demy. This species appears to be somewhat allied to H. hispida,
but is sufficiently distinct. Found by Mr. Lardner Yanuxcm.

H. PERSPECTIVA. — Shell very much depressed, with about six
whorls ; whorls striated across, with raised, parallel, acute lines,
forming strongly impressed sulcai between them. Umbilicus very
large, resembling an inverted spire, in diameter at least equal to
the breadth of the body whorl, and exhibiting distinctly all the
votutions. Diameter three quarters of an inch. Found by Mr.
Lesueur near Lake Erie.

H. LINEATA. — Shell very much depressed, somewhat discoidal.
TVhorls about four, each longer than broad, witb numerous raised,
parallel, equidistant, regular, revolving lines. Suture impressed.
Umbilicus very large, diameter at least equal to the breadth of
the body-whorl, and exhibiting all the volutions distinctly. Aper-
ture longer than wide, lunate. Diameter three-twentieths of an
inch, nearly.

Collection of the Academy.

Found by Mr. Robert E. Griffith, near Philadelphia. Some-
what resembles the last, but is more depressed, and the strito are
transverse, not longitudinal, as in that shell ; the cavity beneath,
also, though of equal proportional diameter, is not proportionally
deep.

H. TiiYROiDUS. — P. 123 et seqq., October 1817. Shell thin,
fragile, convex, umbilicate ; whorls five, obtusely wrinkled, or
rather with equidistant, gradually elevated, obtuse lines ; and
spii'ally striate, with minute, impressed lines ; lip widely reflected,
white and flat before, partially concealing the umbilicus ; pillar-
lip furnished with a very oblique tooth. Breadth four-fifths to
nine-tenths of an inch.

This species very much resembles H. albolabris of Nicholson's
Encyc, Amer. ed., but is umbilicated, and toothed on the pillar-
lip. It is much less common. This shell was indicated in the
American edition of the Encyclopedia, but its characters were not
laid down.

10

11. jnNUTA. — Shell ratlier tliick ; spire convex, little elevated,
with three volutions ; suture well defined, impressed ; whorls
obtusely wrinkled across ; aperture nearly orbicular ; lip much
thickened, reflected, white, distant from the umbilicus ; umbilicus
large, exhibiting the volutions. Breadth less than one-tenth of
an inch. Found under the bark of a decaying oak ; is readily dis-
tinguishable from other species by its small size and conspicuous
lip.

H. LABYRINTHICA. — Shell conic, dark reddish brown, body
lighter ; whorls five or six, with conspicuous, elevated, equidis-
tant, obtuse lines across, forming grooves between them ; apex
obtuse, lip reflected, rounded ; pillar-lip with a large, lamilliform,
elongated tooth, which appears to revolve within the shell, parallel
to the suture ; a smaller raised line revolves nearer to the base
within the shell, but becomes obsolete before it arrives at the
pillar-lip; umbilicus rather large. Breadth one-tenth of an inch.

Found on fungus in decaying wood. This shell is remarkable
for the two much elevated lines, which revolve within the shell
upon the penultimate whoi-1, the upper one larger, and terminating
at the aperture very conspicuously, and resembling a tooth.

Genus Polygyra. — Say.

Journal Acad, vol i. p. 276, anno, May, 1818.

Shell discoidal, more or less carinated on the upper edge of the
whorls, umbilicated ; aperture longer than broad ; lips thickened,
toothed, or folded and continued, folds concave beneath ; pillar-lip
raised above the preceding whoi'l and concave beneath.

Animal granulated, tentacula four, eyes at the tip of the supe-
rior tentacula and retractile ; operculum none.

P. AURicuLATA. — Shell beneath, convex ; whorls five, a little
rounded, crossed by numerous raised equidistant lines, forming
grooves between them ; spire very little raised ; lateral line (ex-
tending from the outer whorl to the apex,) not convex, but some-
what concave ; mouth very unequal, lips prominent above, ad-
prcssed to the preceding whorl beneath ; pillar lip suddenly re-
flected, and pressed into the mouth at an acute angle, beneath
very acutely concave ; outer lip a little more prominent in the
middle, and Avithin the edge protruded into the mouth ; throat
extremely narrow ; suture near the mouth suddenly reflected from

11 i

the preceding whorl, and carinate ; umbilicus dilated, very small
within, and exhibiting a groove on the outer whorl.

Breadth of the female nearly half an inch, of the male about
three-tenths. Inhabits Florida. Cabinet of the Academy. This
curious species we found near St. Augustine, East Florida, in a
moist situation. They were observed in considerable numbers ;
the color is reddish brown, indistinctly banded with whitish lines,
sometimes with darker ones, mouth white.

P. AVARA. — Shell covered with numerous short, robust hairs ;
spire convex ; whorls four, regularly rounded, with hardly elevated
lines forming grooves, which are much more conspicuous near the
mouth ; mouth subreniform, two projecting, obtuse teeth on the
outer lip within, separated by a deep sinus ; outer lip elevated,
equal, describing two-thirds of a circle ; pillar-lip elevated, broadly
but not profoundly emarginate, concave beneath, and connected to
the inner side by an elongated, lamelliform tooth, which is placed
obliquely on the penultimate whorl, near the middle of the mouth ;
lips almost equally prominent, continued ; umbilicus moderate, not
exhibiting the volutions, no groove on the untimate whorl within it.

Breadth quarter of an inch. Inhabits Florida. Cabinet of the
Academy. Animal longer than the breadth of the shell, acute
behind, above granulated and blackish, beneath, and each side,
white.

This we found in the orange groves of Mr. Fatio, on the river
St. John, East Florida ; it is usually covered with a black, earthy
coat, which is probably retained and collected by the hairs. When
unencumbered with this vesture, the shell is of a horn color. It
is by no means so common as the preceding species.

P. SEPTEMVOLVA. — Shell much depressed, discoidal -, spire not
prominent : whorls seven, perfectly lateral, compressed, depressed,
and marked with conspicuous lines and grooves above, a projecting
carina on the upper edge of the body whorl, beneath which the lines
and grooves are obsolete 5 aperture subreniform, not contracted ;
lips equal, elevated, outer one reflected, regularly rounded so as to
describe two-thirds of a circle ; pillar-lip projecting inwards, into
an angle or tooth, which is concave beneath ; beneath the four
exterior volutions equally prominent, transverse diameters equal
to those of the upper surface ; umbilicus central, moderate, at-
tenuated to the apex so as to exhibit the remaining volutions.

12

Breadth, female, two-fiftLs — male, tliree-tehths of an inch. In-
habits Georgia and East Florida. Cabinet of the Academy. A
very common shell in many parts of Georgia, particularly the sea
islands, also in East Florida. We found them numerous under
the ruins of old Port Picolata on the St. John River, and on the
Oyster-Shell Hammocks, near the sea, and in other situations
under decaying palmetto logs, roots, &c.

These shells would have been referred by Linne to the genus
Helix, but as that genus has been limited by Mr. Lamark and
others, to those shells of which the apertures are broader than
long, I cannot with propriety, in the present state of Conchology,
consider them as of that genus. Neither can I refer them to
either of the genera which have been separated from Helix by
Messrs. Lamark, Montfort, &c., by the characters which those
naturalists have given of their genera. They differ from the others
in having the pillar-lip elevated considerably above the surface of
the penultimate whorl, so as to be equally prominent with the
outer lip, with which it forms an uninterrupted continuation, and
by the concavities beneath the lips, formed by the protrusion of a
portion of the shell into the aperture. In this last character it
approaches the genus Caprinus of Mr. Montfort, but diifers in
being umbilicated.

SuccrxEA CAMPESTRis. — Shell oval, very fragile ;, whorls three,
not remarkably oblique, pale yellowish, with opaque, white, and
vitreous lines, irregularly alternating.

Length not quite three-fifths, breadth seven-twentieths of an inch.

This shell is extremely common in many parts of the Southern
States ; it abounds in the sea islands of Georgia in the low,
marshy grounds behind the sand-hills of the coast, where they are
destroyed in great numbers by the annual conflagration of the old
grass. On Amelia Island, East Florida, I found them in great
plenty on the highest sandy ground of the island. On Cumber-
land Island, in Mr. Shaw's garden, I obtained several specimens
from the leaves of radishes.

The resemblance between this species and the oi'cilis is very
great ; it diifers, however, in being less elongated, and of a more
robust form ; the revolution of the spire is much less oblique, the
sliell itself is thicker and less fragile.

Animal whitish • eyes, inferior tentacula, and a line passing

13

from the eyes, disappearing under the shell, black ; a gamboge
colored vitta is visible through that part of the shell which is
opposed to the mouth.
><■ Polyphemus glans. — This shell furnished De Montfort with .
the type of his genus Polyphemus ,; he refers to Bruquiere as
the first describer of it, under the name of Bulimus glans in the
Encycl. Method. The animal has not been described, but wo are
informed that it lives in the immense marshes, formed by the over-
flow of the great rivers that water the vast country of Louisiana.
In the sea islands of Georgia, we found them numerous in the
marshy districts immediately behind the sand-hills of the coast, in
Florida in similar situations, and also on the Oyster-Shell Ham-
mocks, and generally in such situations as are tenanted by Succinea
campestris. The color of the shell on the spire is chestnut brown,
which gradually and very perceptibly becomes paler to the aper-
ture ; aperture occupying about half the length of the shell. On
elevated situations they are small, almost transparent, and of a
fragile consistence. It is only in low, marshy situations that they
attain their greatest size.

Length two inches and two-fifths, breadth one inch nearly.

Animal elongated, as long again as the shell, granulated, tenta-
cula four, superior ones oculiferous, abruptly deflected at tip, be-
yond the eyes ; inferior ones much shorter and deflected at tip ;
lips beneath the tentacula elongated, palpiform, almost as long as
the superior tentacula, retractile, generally more or less recurved,
compressed, attenuated, and acute at tip, and forming a considera-
ble interval between their prominent bases.

When the animal is in motion, the elongated lips are used as
tentacula to feel the way.

Genus Olygyra.
Shell rounded ; aperture longer than broad, semiorbicular,
emarginated by a projection of the penultimate whorl ; external
lip reflected; pillar-lip with obsolete calcareous deposit; umbilicus
none ; columella slightly angulated at base.

Animal terrestrial, operculated ; tentacula two, filiform ; eyes
prominent, placed at the external base of the tentacula ; rostrum
bilabiated at tip, shorter than the tentacula ; foot simple.
(^ 0. ORBICULATA. — Shell subglobular ; spire not prominent, but

14

more than convex ; lateral line somewhat convex ; whorls five,
obsoletely striated across, regularly rounded ; color pale greenish,
yellowish, or slightly tinted with reddish, particularly on the body,
and margined above by an obsolete white line ; on the middle of
the body a white vitta revolves, sometimes obscure or wanting ;
aperture acute above, regularly rounded at the base, and extend-
ing from the centre of revolution or base of the column to an
equidistance between the base and the apex of the spire ; base of
the columellar slightly projecting into an obtuse angle ; exterior
lip whitish, reflected.

Length one-fifth of an inch. Inhabits East Florida. Cabinet
of the Academy. Animal pale ; rostrum and tentacula blackish,
the latter with a white line ; eyes very black, elevated in the form
of a short tubercle ; length about equal to the breadth of the
shell ; foot not broader than the body ; tail rounded, or somewhat
acute ; operculum simple, not spiral, yellowish brown, minutely
granulated.

This species we found in great numbers on what are called
Oyster-Shell Hammocks, near the mouth of the river St. John,
East Florida, in company with Polygyra septemvolva. "When in
motion the tentacula are elevated and depressed alternately, as if
feeling the way.

This shell is certainly a Linnaean Helix, but according to the
improvements which have been made in Conchology since the time
of the Swedish naturalist, by Mr. Lamark and other systematists,
it is at once excluded from that genus and its congeners, by hav-
ing but two tentacula, and by its operculated aperture. With the
genus Cyclostoma, as it now stands, our shell has more affinity
than it has to any other, but a very distinct generic character is
observable in the aperture, which is not orbicular as in Cyclostoma,
but is almost semi-orbicular, greater in length than in breadth, and
the lips widely disunited. In addition to the characters usually
given of the animal of Cyclostoma, Mr. Cuvier remarks that the
tentacula are terminated by obtuse tubercles ; no such appendages
are annexed to the corresponding members of this animal. Upon
these considerations I have thought proper to construct the present
genus.

15

Jour. Acad, vol ii. p. 150, anno, Janunry, 1821.

Helix moltilineata. — Shell thin, convex, imperforated ; of a
brown color, with numerous dark red, revolving lines, which are
minutely and irregularly undulated ; whorls six, with elevated,
subequidistant lines, forming grooves between them ; aperture
lunated, not angulated at the base of the column, but obtusely
curved; labrum contracting the mouth slightly, reflected,
white, more or less distinctly stained by the termination of the
spiral red lines, and adpressed to the body whorl ©ear the base ;
umbilicus covered with a white callus.

Inhabits Illinois and Missouri. Length of the columella about
three-fifths, greatest width rather more than one inch-
Animal granulated, granulce large, whitish, interstices blackish •
foot, beneath, black.

An exceedingly numerous species iu the moist forests on the
margin of Mississippi near the Ohio, and the Missouri as far as
Council Bluff. The red revolving lines are numerous, varying
from four or five to twenty-five or thirty and perhaps still more ;
they are sometime confluent into bands ; when viewed within the
mouth they appear sanguineous.

H. APPRESSA. — Shell depressed, brownish horn color ; whorls
five, depressed, forming an angle on the external one, more acute
near the superior angle of the labrum, with numerous transverse,
elevated, equidistant lines, with interstitial grooves ; umbilicus
covered over with calcareous matter, but concave within ; aperture
moderate ; labrum dilated, reflected, white, margined with brownish ;
near the base, appressed to the body whorl, and covering the um-
bilicus ; a slight projecting, dentiform angle on the inner middle ;
labrum with a strong, prominent, oblique, compressed, white tooth,
which gradually slopes and becomes obsolete towards the um-
bilicus.

Var. a. — Labrum with two projecting angles. Breadth three-
fifths of an inch.

Animal — foot pale ; neck above and each side blackish. In-
habits the banks of the Missouri and Ohio.

This species is very common on the banks of the Ohio below
Galiopolis ; I also found it near Council Bluff. It very much re-
sembles H. tridentata, but the umbilicus is covered over ; the
outer lip at base is flattened upon the shell ; and there is but a

16

single angle upon it. In Lister's Concli. pi. 93, fig. 93, is the
representation of a shell, which is most probably intended for this
species. Lister's figure is quoted in the books for H. punctata,
but as the figure of a different species, (Born. Mus. pi. 14, fig. 17
and 18,) is also referred to as the same, I conclude that two dis-
tinct species have been confounded together under the common
name of punctata; certainly the character from which this name
was taken is never present on our shell. Specimens have been sub-
sequently found by Dr. Thomas McEuen near the Falls of
Niagara.

H. p^y:.LiATA. — Shell depressed, with elevated lines, forming
grooves betweeen them ; epidermis fuscous, rugose with very
numerous minute tuberculous acute prominences : volutions five,
depressed above, beneath rounded, forming an obtuse angle ex-
teriorly, which is more acute near the termination of the labrum ;
umbilicus covered with a white callus ; aperture contracted by the
labrum ; labrum widely reflected, white, two profound, obtuse
sinuses on the inner side above the middle, forming a prominent
distinct tooth between them, and a projecting angle near the mid-
dle of the lip ; labium with a large, prominent, white tooth,
placed perpendicularly to the whorl, and obliquely to the axis of
the shell, and nearly attaining the umbilical callus.

Inhabits Illinois. Length of the column seven-twentieths of an
inch. Greatest breadth, four-fifths of an inch.

Var. a. — A very prominent acu.te carina ; destitute of minute
prominences. Inhabits Ohio. Breadth nearly one inch.

This shell is found on the banks of. the Mississippi in moist
places. It very much resembles H. tridentata, but is destitute of
umbilicus, has a rugose epidermis, and is much larger. It is still
more closely allied to npp?-essa, but its superior magnitude, teeth
and epidermal vesture distinguish it from that species. Specimens
have subsequently been found by Dr. Thomas McEuen near the
Falls of Niagara.

H. INFLECTA. — Spire convex ; volutions five, wrinkled across ;
suture not profoundly impressed ; aperture straight ; labrum re-
flected, bidentate, teeth separated by a profound sinus, the supe-
rior tooth inflected ; behind the lip a profound groove, which
abruptly contracts the aperture in that part, so that although the
lip is reflected, yet its edge is not more prominent than the general

1

>-r

exterior surface of the body wliorl ; at base the lip is adpressed
and covers the umbilicus ; labrum with a large, prominent, oblique,
lamelliform tooth ; umbilicus closed.

Greatest transverse diameter nearly nine-twentieths of an inch.
Inhabits lower Missouri.

The teeth of the labrum somewhat resemble those of tridentata;
but in the form of the groove behind the labrum, and the pillar-
tooth, it resembles H. hirsuia. Several specimens were found, but
all dead shells, and destitute of their epidermis.

H. CLAUSA. — Shell fragile, slightly perforated, subglobular,
yellowish horn color, above convex ; whorls four or five : aperture
slightly contracted by the lip ; lip reflected, flat, white, nearly
covering the timbilicus.

Inhabits Illinois. Greatest breadth from one half to three-fifths
of an inch.

A small and handsome species, which somewhat resembles albo'
labris, but is much smaller, more rounded, and is subumbilicate.
This shell also occurs, though, perhaps rarely, in Pennsylvania.

II. OBSTRICTA. — Shell depressed, with elevated lines forujing
grooves between them ; epidermis pale brownish, naked ; volutions
five, depressed above, beneath rounded, with an acute, projecting
carina ; umbilicus covered with a white callus, indented ; mouth
resembling that of H. palliata.

Inhabits Ohio. Breadth nearlj' one inch.

This species is very closely allied to Helix palliata, but the
epidermis is not covered with small elevations as in that shell, and
the carina is very prominent and remarkable.

H. ELEVATA. — Shell pale horn color, spire elevated ; whorls
seven, regularly rounded; umbilicus none; aperture somewhat
angulated ; labrum dilated, reflected, pure white, at base adpressed
to the body whorl, abruptly nan-owed on the inner edge beneatli
the middle, and continuing thus narrowed to the superior termina-
tion, leaving a projecting angle behind the middle ; labium with a
large, robust, very oblique, subarquated, pure white tooth.

Greatest breadth seven-eighths of an inch. Column nine-six-
teenths of an inch.

Found rather common in the vicinity of Cincinnati, Ohio. It
seems to be distantly related to thyroidus by the tooth on the
labium, but this tooth is much more robust ; it difl'ers much more
3

18

essentially by the much more elevated spire, and by the superior
half of the dilated lip being abruptly narrowed so as to form a
prominent angle near the middle. It is also a much thicker shell.
H. INTERNA. — Shell yellowish red ; volutions six or eight ;
whorls with regular, equidistant, elevated, obtuse lines across
them, separated by regular grooves ; lines obsolete beneath ; spire
convex, little elevated ; aperture very straight, transverse, less
than one half of the longitudinal diameter ; labrum not reflected ;
within, upon the side of the labrum, two prominent, lamelliform
teeth, of which the superior one is largest, and neither of them
attain the edge of the lip ; region of the base of the columella
much indented ; umbilicus obsolete or wanting.

Transverse diameter more than three-tenths. Height of the
columella about three-twentieths of an inch. Inhabits Lower Mis-
souri.

Of two specimens which I obtained, the larger one had six
volutions, and the smaller one had eight ; the superior tooth in the
larger one was concave towards the base of the shell. It is a
remarkable and very distinct species.

H. CHERSINA — Shell subglobose- conic, pale yellowish white,
pellucid, convex beneath ; volutions about six, wrinkles not dis-
tinct ; spire convex-elevated ; suture moderate ; body whorl
slightly carinated on the middle ;. mouth nearly transverse, un-
armed, the two extremities nearly equal ; labrum simple : umbilicus
none.

Inhabits the Sea Islands of Georgia. Breadth one-tenth of an
inch. Cabinet of the Academy.

A very small species. But one specimen occurred in a cotton
field. It is rather larger than H. labyrinthica.

H. GUi.ARis. — Shell subglobose, pale yellowish horn color ;
polished, pellucid, beneath near the aperture whitish-yellow opake;
volutions six or seven, with prominent, somewhat regular wrinkles ;
spire convex, a little elevated ; suture moderate ; labrum not re-
flected ; throat far within upon the side of the labrum, bidentate ;
teeth lamelliform, of which one is oblique and placed near the
middle, and the other less elongated, placed near the base ; um-
bilicus none.

lireadth more than one-fourth of an inch. Inhabits Ohio and
Pennsylvania.

19

In general form it resembles H. ligera, but may be distinguished
•by the absence of umbilicus, and, upon particular examination, by
the teeth, which are situated far within the aperture. In the col-
lection of the Academy.

H. LIGERA. Shell subglobose, pale yellowish horn color,
polished ; body whorl pellucid, yellowish white, opake beneath
near the aperture ; volutions rather more than six, all except the
apicial one, wrinkled across ; spire convex, a little elevated ; um-
bilicus very small ; suture not deeply impressed ; labrum not
reflected.

Inhabits Missouri. Greatest length three-tenths, oblique length
less than nine-twentieths, transverse diameter less than eleven-
twentieths.

Approaches nearest to H. glaphyra, but is readily distinguished
by the greater convexity of the spire, and the smaller umbilicus.
Rather common. In Lister's Conch, on pi. 81, fig. 82, a shell is
represented which may be intended for this species.

H. SOLITARIA. — Shell subglobose, with two or three revolving,
rufous lines ; spire conico-convex ; volutions five and a half, wrin-
kled across and rounded ; suture rather deeply impressed ; aper-
ture wide, embracing a rather small portion of the penultimate
whorl ; labrum noi reflected ; umbilicus large, distinctly exhibit-
ing all the volutions to the apex.

Grreatest transverse diameter nearly one and one-fifth of an inch.
Inhabits lower Missouri.

But a single specimen was found ; it was a dead shell, destitute
of its epidermis. It is a very distinct species.

H. JEJUNA. — Shell subglobular, glabrous, pale reddish brown ;
volutions five, slightly wrinkled, regularly rounded ; spire con-
vex ; suture rather deeply impressed ; aperture dilate lunate ;
labrum a little incrassated within, not reflected ; umbilicus open,
small.

Breadth rather more than one-fifth of an inch. Inhabits the
Southern States.

x\nimal — light reddish brown, with a granular surface, longer
than the breadth of the shell ; oculiferous tentacula elongated, and
rather darker than the body.

This shell is very closely allied to H. sericea of Southern
Europe, but it difiers from that species in being destitute of the

20

hirsute vesture. I found several specimens of jejuna, during an
excursion some time since into East Florida, at the Cow Fort ou ,
St. John Eiver. It is in the collection of the Academy,

II. CONCAYA. — Shell much depressed, suborbicular, horn color,
or whitish, immaculate ; volutions five, irregularly wrinkled across,
more convex beneath ; suture distinctly impressed ;. umbilicus
very large, exhibiting all the volutions to the summit distinctly ;
aperture large, short ; labrum towards the base very slightly and
inconspicuously reflected.

Inhabits Illinois and Missouri. Greatest width seven-tenths of
an inch.

Found in moist places near the Mississippi Eiver, on the Mis-
souri as high as Council Blufi, and on the Sea Islands of Georgia.
It is a much depressed shell.

H. DEALBATA. — Shell couical, oblong, thin and fragile, some-
what ventricose ; volution G-7, wrinkled across, wrinkles more
profound and acute on the spire ; spire elevated, longer than the
aperture, sub-acute ; aperture longer than wide, labrum not re-
flected ; umbilicus small and profound.

Length more than three-fourths of an inch, breadth nine-twen-
tieths of an inch. In the Cabinet of the Academy and Philadel-
phia Museum. Inhabits Missouri and Alabama.

In outline it resembles a Bulimus. Four specimens of this
species were sent to the Academy from Alabama, by Mr. Samuel
Hazard ; and a single depauperated specimen was found by myself
on the banks of the Missouri.

H. PROFUNDA. — Shell pale horn color ; spire convex, very little
elevated ; whorls five, regularly rounded, and wrinkled trans-
versely ; body whorl with a single revolving rufous line, which is
almost concealed on the spire by the suture, but which passes for
a short distance above the aperture ; aperture dilated ; labrum
reflected, white, and excepting near the superior angle, flat ; a
slightly projecting callus near the base, on the inner edge ; um-
bilicus large, profound, exhibiting all the volutions to the apex.
Transverse diameter nineteen-twentieths of an inch.

Var. a. — Multilineated with rufous. Var. b., rufous line obso-
lete. Inhabits Ohio, Mississippi and Missouri banks.

A pretty shell, neatly ornamented with the rufous zone ; the
spire is very much depressed. Specimens occurred near Cincin-

21

nati on the Ohio, and at Engineer Cantonment at Council Bluff,
on the Missouri.

Besides the above species, I have observed in the western
regions the following known species, which I described in the
American edition of Nicholson's Encyclopasdia, and in the Journal
of the Academy.

H. ALBOLABRis. — Conmiou as far as Council Bluff.

11. TiiYROiDUS. — On the banks of the Ohio, Mississippi and
Missouri. The animal is of a pale whitish or yellowisli color,
immaculate.

H. ALTERNATA. — On the banks of the Ohio, Mississippi and
Missouri Kivers ; this species varies in being somewhat larger, and
in having a rather more elevated spire. The animal is of a dirty
yellowish orange color. The foot obtusely terminated behind,
head and tentacula pale bluish, eyes blackish. Shell nine-tenths
of an inch in breadth.

H. HiRsrTA. — Common as far as Council Bluff.

H. LABYRINTHICA. " " "

H. MINUTA. " " *'

H. PERSPECTIVA. — Occasionally occurs on the banks of the
Missouri, and other western streams, and in some parts com-
mon.

PoLYGYRA PLICATA. — Shell convex beneath, depressed above,
spire slightly elevated ; whorls five, compressed, crossed by nu-
merous raised, equidistant lines, which form grooves between
them ; aperture subreniform, labrum reflected, regularly arquated
describing two-thirds of a circle ; within two-toothed, teeth not
separated by a remarkable sinus ; labrum with a profound dupli-
cature, which terminates in an acute angle at the centre of the
aperture ; beneath exhibiting only two volutions, of which the
external one is slightly grooved near the suture.

Inhabits Alabama. Breadth one-fourth of an inch. Cabinet of
Academy.

This species is about the same size as P. avara, but, besides
other characters, it is sufficiently distinguished by the acute fold
of the labrum. It was sent to the Academy by Mr. Samuel
Hazard.

Pupa Arjiifera. — Shell destral ; oblong oval, or somewhat

22

obtusely fusiform ; suture distinct ; whorls six, obsoletely wrin-
kled ; aperture longitudinally subovate ; exterior lip reflected, but
not flattened, interrupted above by the penultimate whorl, and
with five teeth, of which the superior one, and that which precedes
the basal one, are smallest ; labrum with an undulated lamelliform
tooth, its anterior extremity little elevated, but elongated so as
almost to join the superior extremity of the exterior lip.

Length three-twentieths of an inch. Inhabits Upper Missouri.

Var. a. — The two smaller teeth obsolete or wanting. Var. b. —
The basal tooth obsolete or wanting.

Very distinct from corticaria, it being a much larger and pro-
portionally more dilated shell ; and with that species and the next
seems to belong more properly to the genus carychium of Muller
and Ferussac.

P. RUPicoLA. — Shell dextral, attenuated to an obtuse apex,
white ; whorls six, glabroiis ; suture deeply impressed ; labrum
bidentate ; superior tooth lamiform, emarginate in the middle, and
at the anterior tip obtusely uniting with the superior termination of
the labium ; inferior tooth placed upon the columella, and extend-
ing nearly at a right angle with the preceding ; labrum tridentate,
teeth placed somewhat alternately with those of the labium, infe-
rior tooth situated at the base and immediately beneath the inferior
tooth of the labium.

Length about one-tenth of an inch. Inhabits East Florida.

I formerly found it abundant on the banks of St. John River,
in East Florida, and more particularly under the ruins of Fort
Picolata, under stones, &c.

It is about the size of P. corticaria, and considerably resembles
that species, but is sufficiently distinguished by the circumstance
of its gradually decreasing in diameter from the body whorl, to its
obtuse tip ; and, in the character of the mouth, it is widely dis-
tinct.

SucoiNEA ovALis. — (Jour. Acad. Nat. Sc. vol. i. p. 15.) A
large variety of this species is found very common on the Missouri,
of the length of about four-fifths of an inch ; I observed one speci-
men which was upwards of an inch long.

Cyclostoma MARGiNATA. — Shell turreted, pale horn color, or
dusky, obsoletely wrinkled across ; suture rather deeply impressed ;
volutions six ; aperture mutic, suboval, truncated transversely

23

above by the penultimate whorls, nearly one-third the length of
the shell ; labium nearly transverse, color of the exterior part of
the shell ; labium equally and widely reflected, thick, white, um-
bilicus distinct.

Inhabits Upper Missouri. Length one-fifth of an inch.

Size of Paludina lapidaria. Lister represents a species on plate
22, fig. 19, which, although rather larger, may possibly be intended
for this species ; he denominates it " Buccinum exigium, rufum,
quinq orbium." This shell does not perfectly correspond in
character with Cyclostoma ; it is most probably a Pupa, and if so,
the specific name must be changed, as the present name is pre-
occupied in that genus.

Journal of the Academy. Vol. ii., page 370, anno, June, 1822.

Helix irrorata. — Shell imperforate, depressed, subglobular,
pale reddish brown, with very numerous small white spots, and
about four deeper brown obsolete bands ; whorls rounded, nearly
five in number, wrinkles obsolete on the body whorl, more distinct
on the spire ; spire depressed, convex ; suture declining much
near the mouth ; aperture on the side of the labrum, within some-
what livid ; labrum reflected but not flattened, and not abruptly
contracting the aperture, white before and yellowish behind ; near
the junction with the columella is a callus, which does not rise into
an angle.

Length from the apex to the base of the columella, three-fifths
of an inch nearly. Greatest breadth one and one-tenth of an inch.
Inhabits Northumberland county, Pennsylvania. Cabinet of Mr.
William Hyde.

This species may be compared with the H. lac tea, Muller and
Ferussac ; the spire is rather more prominent, the white spots, or
rather abbreviated lines are similar in form, size and number, but
its labrum preserves the same color with the exterior of the shell,
and the livid tint of the inner portion of the body whorl is very
pale ; the posterior face of the reflected labrum is immaculate, and
its callus base is not angulated ; the aperture is much less wide
than that of ladea; and in Mr. Hyde's specimen, a small fissure
remains near the umbilicus. It still more closely resembles a
variety of a shell which inhabits the Island of Candia, but that

24

species lias always a white base, being immaculate beneath the
inferior band.

H. INORNATA. — Shell subglobose, pale yellowish horn color,
polished ; whorls five, rounded, -wrinkled ; spire convex ; suture
not deeply impressed ; umbilicus small, profound ; aperture wide,
at the junction of the labia with the penultimate whorl shorter
than the width of the mouth ; labrum simple.

Inhabits Pennsylvania. Grreatest width less than seven-tenths
of an inch.

This species has a strong resemblance to H. ligera, but in addi-
tion to its superior magnitude, its aperture is proportionally wider,
a character which of course gives the whorls a greater breadth ;
the whorls are also fewer in number, and the distance between the
terminations of the lips is very perceptibly less than the width of
the aperture, the reverse of which obtains in the ligera.

IT. INDENTATA. — Shell depressed, pellucid, highly polished ;
whorls four, with regular, distant, subequidistant, impressed lines
across, of which there are about twenty-eight to the body whorl,
all extending to the base ; suture not deeply indented ; aperture
rather large ; labrum simple, terminating at its inferior extremity
at the centre of the base of the shell ; umbilicus none, but the
umbilical region is deeply indented.

Greatest breadth one-fifth of an inch. Animal blued-black,
immaculate.

My cabinet and that of Mr. Wm. Hyde. Several specimens
occurred at Harrigate, the country residence of my friend Mr.
Jacob Gilliams, adhering to stones and logs in moist places. Mr.
Hyde obtained many individuals in New Jersey. It may readily
be mistaken for H. arborea, but it. is destitute of the umbilicus,
instead of which there is an indented centre to the base, in which
the labrum terminates. The spire is very much depressed, and
the surface prettily radiated by distant impressed lines, the inter-
stices being perfectly smooth.

H. LINEATA. — (Vol. i., p. 18.) On examination of several in-
dividuals of this species, I have ascertained that a character exists
in this species that was altogether wanting in the specimen from
which I drew out the description published in the first volume of
this work. As the shell is somewhat translucent, two pairs of
white teeth, remote from each other, may be observed through the

25

body whorl of the shell. One pair of these teeth is placed in the
throat, so near to the labrum as readily to be seen by looking in
at the aperture. These teeth are nearly equidistant from each
other, and from the extremities of the labrum. The other pair is
placed so far within the shell as not to be seen at all from the
aperture.

I found several specimens in a humid situation at Harrigate.
iJ-'W BuLiMUS MUTILATUS. — Shell turriculated, pale reddish brown ;
whorls four, longitudinally striated with irregular elevated lines
or wrinkles, which are a little more prominent near the sutures ;
suture not deeply indented ; apex widely truncated ; labrum
whitish, destitute of calcareous deposit ; body whorl more than
double the width of the truncated apex; spire one and a half
times longer than the aperture. Length less than one inch ; width
less than half an inch ; length of the aperture two-fifths of an
inch.

Inhabits South Carolina, about Charleston.

This curious shell is the first and only species of the genus
Bulimus, native of the United States, that I have yet seen. I am
indebted for it to the researches of Mr. Stephen pjlliott, of
Charleston, who informs me that it is there found in gardens. In
the truncated form of the apex of the spire, this species resembles
the decollata, conso/idata, ti~uncata, and Pvpa torticollis, &c., but
it is sufficiently distinct from the former, to which it is more
closely allied than to the others, by its less cylindrical and more
conic form, being much more robust in its figure and less elongated ;
the aperture is consequently wider, and forms a greater proportion
of the total length. It does not change to an opake white after
the death of the animal, as the decollata generally does.

Pupa contracta. — Shell dextral, short, subovate, white ; apex
obtuse; whorls five; umbilicus distinct; aperture regularly
orbicular, complete, the lamina of the labium being elevated
above the surface of the preceding whorl, and joining the extremi-
ties of the labia ; labium with a large, elongated, prominent tooth,
which is concave on the side towards the labrum ; labrum
bidentate, a large tooth or fold far within the throat, caused by
the fold of the umbilicus ; throat much contracted by the large
tooth of the labrum into the form of a horse-shoe.

Total length less than one-tenth of an inch. Inhabits Virginia.
4

26

This is a short, wide species, sufficiently distinct from others,
and readily distinguished by the lamina of the labrum being much
elevated, and by the magnitude of the tooth of the labium. I
obtained two specimens at Occoquan, under a pile of bricks and
rubbish. This species probably belongs to the genus Carychium.

P. EXIGUA. — Shell dextral, tapering, oblong, with minute
grooved lines ; apex obtuse ; whorls five ; suture deeply impressed ;
labium bidentate, superior tooth situate rather beneath the middle
of the lip, inferior tooth small, placed on the columella ; labrum
mutic, reflected, but not flattened ; umbilicus distinct.

Length more than one-twentieth of an inch.

This is the smallest species that I have seen. Numerous speci-
mens of it were found near this city by Mr. William Hyde, and I
have obtained many at Harrigate. Its aperture resembles that of
Pupa (Carychium) corticaria, but the superior tooth of the labium
of that shell is situate much nearer to the superior termination of
the labrum than the corresponding tooth of this diminutive species.
It is probably a Carychium.

Genus Vertigo — Muller and Ferussac.

P. (vertigo) ovata. — Shell dextral, subovate, brown ; apex
obtuse ; whorls five, glabrous ; suture not very deeply impressed ;
body whorl indented near and upon the labrum ; aperture semi-
oval ; labium five-toothed, of which three are situate on the trans-
verse portion of the lip, parallel to each other, equidistant, the
superior and inferior ones being small, the latter sometimes
obsolete, the intermediate one lamelliform, prominent, and the two
others situate on the columella, approximate, extending at right
angles to the three preceding ones, the superior one oblique and
smaller ; labrum reflected, but not flattened, bidentate, teeth
lamelliform, prominent ; umbilicus distinct.

Length less than one-tenth of an inch. Breadth nearly one-
twentieth of an inch.

Animal — tentacula 4,wo, rather long and thick, cylindrical-
obconic, retractile, with a rounded oculiferous extremity ; foot
white; head and neck, as far as the mantle, black.

Inhabits Pennsylvania Numerous specimens were discovered
by Mr. William Hyde in the vicinity of this city, and I obtained

27

others at Harrigate. The smallest teeth of the labium are some-
tiuies obsolete.

V. PENTODOX. — Shell dextral, subovate, "whitish horn color ;
apex obtuse, whorls five, glabrous, convex ; suture not very deeply
impressed ; aperture semioval ; labium two-toothed, of which a
single very prominent one is on the middle of the transverse por-
tion or true labium, and the other is remote, much smaller, and
placed in the basal angle of the columella: labrum regularly
arquated, tridentate, tooth nearest the base very small, and placed
near the smaller tooth of the columella, the two others larger,
subequal ; umbilicus distinct.

Length less than one-tenth of an inch.

Animal — tentacula two, rather long and thick, cylindrical
obconic, retractile, with a rounded oculiferous extremity ; two
hardly elevated truncated tubercles instead of the anterior tenta-
cula : foot white ; head and neck, as far as the mantle, black.

Inhabits Pennsylvania. The lower tooth of the labrum is some-
times obsolete.

Melampus obliquus. — Obconic, reddish brown, rather thick ;
spire very little elevated ; whorls eight or nine, wrinkled across ;
labium Avith two very distinct teeth, and an intermediate and
equidistant slight obtuse prominence ; inferior tooth very oblique,
terminating at the base ; labrum with about eight teeth or striae,
which terminate on the margin ; base of the aperture a little
contracted by the basal tooth.

Length more than seven-twentieths of an inch. I am indebted
to Mr. Stephen Elliott for this species, who obtained it on the
coast of South Carolina. It is closely allied to Bulimus monile,
Brug., but it has no appearance of bands, which distinguish that
shell. In the collection of the Academy are specimens from the
West Indies.

In the Journal of the Academy, vol. v., page 119, et seqq., anno, 1825.

Helix pallax. — Spire convex ; volutions five, with elevated
lines forming grooves between them ; labrum reflected, contracting
the aperture, bidentate ; teeth separated by a profound sinus ;
superior tooth inflected into the mouth ; inferior tooth situated
near the base ; labrum with a large, prominent, oblique, lamelliform

28

tooth, curving downwards so as nearly to reach the termination of
the labrum ; umbilicus open, exhibiting the volutions.

Greatest transverse diameter nine-twentieths of an inch.

This resembles the tridentata, JVob., but the upper tooth of the
labrum is much inflected, the spire is more elevated, and the size
is less considerable ;. in the former character it coincides with H. '
injlecta, JV'ob., but that shell has the umbilicus closed.

Presented to the Academy by Messrs. Hyde and Mason, who
found it in the vicinity of Philadelphia, where it is not uncommon.

Since the above was written, I received a specimen from Mr.
Stephen Elliott, of South Carolina, fully equal in size to the
tridentata.

H. EGENA. — Shell convex, polished : whorls five, not distinctly
wrinkled, rounded ; aperture rather narrow, transverse ; labrum
simple, at its inferior extremity terminating at the centre of the
base of the shell ; umbilicus none, but the umbilical region deeply
indented.

Breadth more than one-tenth of an inch.

This shell was found by Mr. John S. Phillips o"n the banks of
the Delaware River, about ten miles from Philadelphia. It is
much more elevated and not so broad as H. arborea, JVobis.; the
aperture also is of a different shape. It is much broader than the
H. ckersina, JYob.

BuLiMUS MULTiLiNEATUS. — Shell conic, not very obviously
wrinkled ; whorls not very convex, yellowish white, with trans-
verse entire reddish brown lines ; a blackish subsutural revolving
line ; suture not deeply indented, lineolar ; apex blackish ;
umbilicus small, surrounded by a broad blackish line ; columella
whitish ; labrum simple, blackish.

Length less than seven-tenths of an inch. Greatest breadth
less than seven-twentieths of an inch. This species was found by
Mr. Titian Peale on the southern part of East Florida.

Pupa fallax. — Shell turreted, pale horn color ; wrinkles
rather obtuse, hardly prominent ; suture rather deeply impressed ;
volutions nearly seven, a little convex ; apex somewhat obtuse ;
aperture unarmed, suboval, truncated above by the penultimate
whorl, less than one-third the whole length of the shell ; labrum
nearly transverse, color of the exterior part of the shell ; colum-
ella reflected, rectilinear, longitudinal, forming an obvious though

29

a rounded ande with the labrum and the labium : labrura hardly
reflected ; umbilicus narrow.

Length more than three-tenths of an inch. For this species I
am indebted to Dr. T. W. Harris, of IMilton, Massachusetts.

It closely reseuibles P. marginata, A^ob., but is much larger, and
the labrum is not widely reflected. When viewed in front it has a
reflected appearance, but the opposite view presents only a very
limited escurvature.

AcHATiNA SOLIDA. — Shell conic, rather elongated, nearly
smooth, or with distant wrinkles, polished, yellowish, paler
towards the apex, which is white ; rather ponderous ; whorls
about seven ; spire prominent ; mouth rather small ; labrum on its
inner submargin thickened ; columella hardly truncated, with a
somewhat prominent ridge on the inner side near the base.

Length two and a half inches. This species was found by Mr.
Titian Peale in the southern part of East Florida, where he also
obtained the A. jiammigera, Fer., and vexillum, Humph., or their
analogues, in plenty. In outline it bears some resemblance to
Lister's fig. 9, of plate 14, but is much smaller. It appears to be
rare, but one specimen having been brought home by Mr. Peale.

Cyclostoma dentatum. — Shell conic, cylindric, truncate at
tip ; whorls three or four, slightly convex, cancellate, with fine,
regular, subequal, longitudinal, and transverse elevated lines;
superior edge fimbriated, with prominences extending over the
suture ; one or more rufous revolving lines, sometimes obsolete j
labrum somewhat reflected, white ; umbilicus distinct.

Length less than one-half inch.

For this species we are indebted to the researches of Mr. T.
Peale in Florida. It is the only true species of Cyclostoma yet
found within the limits of the Union. This species is somewhat
like the Turbo crenatus, Linn., but that shell is not said to be
truncated at tip, and has a keeled base.

No. 3. — In the Appendix to Long'f Second Expedition to tlie St. Peter's River, the fol-
lowing species were described, anno, 1824.

Helix harpa. — Shell conic, reddish brown ; whorls four,
convex, with numerous elevated, subequidistant, equal, lamelli-
form, acute lines across, the interstitial spaces flat and wrinkled ;
aperture suborbicular, truncated by the penultimate whorl, and

30

very little oblique ; labium simple ;, umbilicus small, nearly con-
cealed by the base of the labium.

Length rather more than one-tenth of an inch. Inhabits the
North-west Territory.

The elevated lines on this shell give it a very handsome appear-
ance, and readily distinguish it from any of our native species
that I have seen. The European analogue is the aculeata of
Muller, but our shell is destitute of recurved points on the lamel-
liform lines. PI. 15, f. 1.

H. PORCINA. — Shell depressed, yellowish brown ; epidermis
rugose, with minute, very numerous bristles ; whorls rather more
than four, depressed above, beneath rounded, forming a very
obtuse angle rather above the centre of the v»'horl ; umbilicus
open, lathei small, profound ; labium simple.

Breadth rather more than three-tenths of an inch. Inhabits
Noith-west Territory. PI. 15, f. 2.

H. FRATERNA. — Shell couvex, brownish horn color, minutely
hirsute ; whorls five, rounded ; umbilicus partially or entirely
closed by the termination of the labrum ; region of the umbilicus
indented ; aperture much contracted by the labrum ; labrum
reflected, white, unarmed ; its outer edge not projecting beyond
the curve of the whorl : its inferior angle extends to the centre of
the base of the shell ; labium with a strong, prominent, com-
pressed, white tooth.

Breadth one-third of an inch. Inhabits Pennsylvania.

I obtained a specimen of this shell several years ago, but sup-
posing it to be an accidental variety of the hirsuta, I laid it aside
without further notice. Since then, however, Messrs. Hyde and
Mason have pi'esented numerous specimens of the same species to
the Academy, having found it rather common ; I therefore no
longer hesitate to consider it as a distinct species. It resembles
Helix monodon of Mr. Backett (Tians. Linn. Soc. London, vol.
xiii., pi. 5,) in the confoimation of the aperture, but that shell is
represented as being largely umbilicated, and its labrum does not
extend near to the centre of the base, as it does in our shell. PI.
15, f. 3.

11. DiODONTA. — Shell somewhat depressed ;. spire convex, very
little elevated ; whorls five, rounded, regularly, but not promi-
nently wrinkled, and grooved transversely ; aperture moderate ;

31

labrum reflected, with a slightly projecting dentiform callus near
the base on the inner edge ; labium ^vith an oblique tooth on the
middle ; umbilicus rather large, profound, exhibiting all the
volutions.

Breadth rather more than seven-tenths of an inch. This shell
inhabits the State of New York. It is closely allied to H. pro-
funda, Jfoh., but may be distinguished by its smaller size and
armed labium. Its aperture also is much more dilated than that
of the profunda, PI. 15, f. 4.

H. PERSPECTIVA, Nob. — Is common in the North-west Terri-
tory ; it varies in being smaller, and in the circumstance of the
labrum embracing a somewhat smaller portion of the penultimate
volution.

H. ARBOREA, Nob. — Common in this Territory.

H. CHERSINA, Nob. — A variety of this species is not uncommon
in the North-west Territory. It differs in the greater rotundity
of the upper part of each whorl, and in the somewhat less rounded
or more flattened figure of the labrum. It may, however, prove
to be a distinct species, when many specimens of chersina can be
had to compare with it.

H. Alternata, Nob. and H. albolabris. — On our return
homewards, these two species were not found until we arrived in
the secondary country towards the eastern extremity of Lake
Superior.

H. THYROTDTTS, NoB. — Falls of Niagara.

H. LIGERA, Nob. — North-west Territory.

Vitrina pellucida of Authors. — This shell was first found
near Cold water Lake in latitude 48 f north, under stones, fallen
timber, &c. It afterwards frequently occurred in similar situa-
tions, until we approached Lake Superior, when it was no more
seen. Like its congeners, the inhabitant is much too large to
retract within the shell, and a great portion of the body is there-
fore constantly exposed. No species of this genus has been
hitherto found in this country ; the discovery of this shell is
therefore the more interesting. The specimens which we collected
do not appear to differ in any respect from those of Europe.

BuLiMUS lubricus of Authors. — The species occurred under
stones, &c., on the shores and islands of Lake Winnepeck and
Lake of the Woods. It is altogether similar to the European

32

specimens of this species, excepting that the labi-nra is somewhat
more transverse.

Pupa modesta. — Shell dextral, suboval, minutely wrinMed ;
apex obtuse ; whorls six ; umbilicus distinct ; aperture obliquely
subovate ; labium with a prominent, compressed, seraioval tooth,
equidistant from the extremities of the labrum, and a somewhat
conic one rather below the middle of the columella ; labrum not
reflected, joining the preceding whorl at its upper extremity with
a curve; bidentate, lower tooth placed opposite to that of the
middle of the labium, the others smaller and placed a little
above.

Length less than one-tenth of an inch. Inhabits the North-
west Territory. PI. 15, fig. 5.

Var. a. — The smaller tooth of the labrum obsolete or wanting.

SucciNEA AVARA. — Shell suboval, pale reddish-yellow, subdia-
phanous, fragile, covered with an earthy crust ; whorls three,
minutely wrinkled ; body whorl very large ; spire small ; aperture
large, subovate, about two-thirds of the whole length of the shell.

Length three-twentieths of an inch. Inhabits the North-west
Territory.

This small species of Succinea occurs in humid places, very
frequently under stones and near the water. The shell is always
completely encrusted with a coating of earth. It may at once be
distinguished from either the ovalis or campestris by its very small
size. PI. 15, fig. 6.

S. OBLIQUA. — Shell oblong-oval, nearly pellucid, pale amber-
colored ; whorls three, very obliquely revolving, distinctly wrinkled ;
spire a little prominent ; aperture suboval, somewhat oblique.

Length seven-tenths of an inch ; length of the aperture less
than one-half inch. Inhabits Pennsylvania.

Of this fine species, found in the vicinity of Philadelphia, many
specimens were some time since presented to the Academy Nat.
Sc. by Messrs. Hyde and Mason, and we obtained a specimen near
the Falls of Niagara. It may at once be distinguished from
either the ovalis or campestris by the much greater obliquity of
the revolutions of its whorls. It is very much like the helix
putris of Linn., but it is more than double the size of that species.
It may, however, be a variety of that shell. PI. 15, fig. 7.

33

(Say's Americnn Conchology, vol. i., No. II, April, 1831.)

Helix albolabris. — Shell convex, imperforated, immaculate,
pale reddish brown ; volutions about five and a half, with rather
obtuse wrinliles, crossed by very minute lines, more obvious on
the body whorl than on the spire ; suture distinct, not very deeply
impressed ; labrum abruptly contracting the mouth, rather widely
and abruptly reflected, flattened in the plane of the mouth, white,
rather deeply and abruptly more arquated at base. Plate 13,
fig. a.

Synonyms.

Helix albolabris. Nobis — Nobis. Am. Ed. of Nichols. Encycl.,
vol. iv. Ferussac, Hist. Nat., pi. 43, f. 1 to 5.

Cochlea virginiana, subalbida, mediocris. circiter quinis orbibus,
parum altis ad claviculam circumscripta. Lister, Synops. pi. 47,
f. 45.

This is one of our most common species, less abundant, however,
in the ^\''estern than in the Eastern portion of the United States ;
and is an inhabitant of an extensive region, extending from
Canada to South Carolina, whence an individual was sent me by
the late Mr. Elliott ; and it is probably found even in Florida. It
belongs to the genus Acavus, Mont fort, which he separates from
Helix, in consequence of being destitute of umbilicus.

A species of the Linnaean Genus Acarus infests the animal. I
have frequently seen this little active parasite, running out and in
the respiratory cavity, when the orifice was open to receive the
air. Sometimes it is excluded for a few moments by the closing
of the orifice, but it courses nimbly about until another dilatation
of the pulmonary aperture receives it into the interior. An
analogous species inhabits the Helix nemoralis, L. of Europe,
according to Kirby and Spence.

H. THYROIDUS. — Shell rather thin, convex, umbilicate, pale
reddish brown, immaculate ; volutions five, wrinkled ; suture
distinct, but not very deeply impressed ; labrum abruptly con-
tracting the aperture, rather widely reflected, flattened in the
plane of the mouth, excepting the superior third, and -white ;
umbilicus narrow, distinct ; labium with an oblique white tofith,
rather above the middle, and not very prominent,
5

34

Synonyms.

Hdix thyroidus. — Nobis, Journ. Acad. Nat. Sc. vol. i., p. 123.
Nicholson's Encycl. (Am. edition.)
Ferussac, Tabl. System, p. 33.

Cochlea umbilicata, capillaceis stryis per obliquum donata.
Unico dente ad fundum oris. List. Synopsis Conch, pi. 91, f. 91.

The following synonyms are from Ferussac, Tab. Sys. Petiver,
Gazophyll. t. 405, f. 4 — Philos. Trans, vol. xx., p. 375.

Cochlea terrestris Virginiana, &c. Schroter, Enleit, ii., p. 192,
No. 60.

A very abundant species, much more numerous than the pre-
ceding in this region. It has certainly a general resemblance to
the albolnbris, but it is smaller, always umbilicated ; the labrum,
near its junction with the penultimate whorl is not so flatly
reflected, and the tooth of the labrum is very conspicuous. It
belongs to Montfort's genus Cepolis, plate 13.

Glandina truncata.

Synonyms.

Buccinura striatum. Chemnitz, ix., t. 120, fig. 1028, 1029,
(Ferussac.)

Bulla truncata. Gmel. Dillwyn, (Fer.)

Polyphemus glans. Nobis. Nicholson's Encycl.

Helix rosea. Ferussac.

e flumine quodam Carolinoe. List. Conch. 1059, fig. 4.

Shell pale reddish brown, or slightly tinted with rosaceous,
often deepest on the spire, gradually becoming paler to the aper-
ture ; spire rather prominent, somewhat mamelary at tip ; volutions,
five or six, very obviously wrinkled ; two or three apicial volutions,
almost destitute of wrinkles: suture well defined, irregularly
crenulated ; columella decidedly incurved.

When in the Sea Islands of Georgia and Florida with Mr.
Maclure, we found this species in great abundance in marshy dis-
tricts immediately behind the sand hills of the coast. In Florida
they also occurred on elevated mounds of oyster shells, called
hammocks, and generally in such situations as are tenanted by
Succinea cnmpestris, JVob. On these elevations they were gene-
rally small, translucent, and of a fragile consistence, and we
observed that they obtained their greatest development only in

35

the low marshy places. Mr, Elliott, of Charleston, South Carolina,
since favored Ifao with living specimens from near that city, where,
he informed me, they are not very abundant. These individuals
refused such vegetable food as I could procure for them, (in
December,) but one of them devoured the animal of a Helix which
was in the vessel that contained them. Lister's figure above
quoted is referred to with doubt by Ferussac, in his Tab. Syst. p.
57, for his Helix goniostoma.

In Lesueur's collection are specimens which he found at St.
Francisville on the Mississippi, and Mr. Titian Peale found speci-
mens on the Florida Keys. So that, taking the above-mentioned
localities into consideration, this shell seems to be an inhabitant
of the whole alluvial region, from at least the middle of South
Carolina to the Mississippi, and perhaps even still farther south.

In the American edition of Nicholson's Encyclopaedia T pub-
lished an account of this species under the name of Polyphemus ^_
glans ; I supposed it to be that species, as Montfort says it lives in Sfi^ >/<^
the interior of Louisiana. But Ferussac says that our shell is not /^
the glans of Bruquiere, which is not an inhabitant of Louisiana,
but of St. Domingo. In his general observations, as well as in a
letter to me, he says it is the Buccinum striatum of Chemnitz, and
Bulirnus striatus of Bruquiere ; whereas, in his enumeration of the
species, he rejects the name of striatus entirely, and places those
two synonyms under two separate species, to which he gives new
names. I think, however, that this name cannot, in justice to
Muller — from whom Bruquiere adopted it — be applied to our spe-
cies, inasmuch as he had reference to the South American species.
As it is, therefore, neither the glans nor the striata, I adopt the
name applied byGmelin,for which I am indebted to the synonyms
collected by Ferussac, on whose accuracy and opportunities for
comparison in this instance I wholly rely, when, in my own opinion,
the reference would, but for this authority, be doubtful.

No. 4.— March, 183:.
Helix clausa. — PL 37, fig. 1. As in Journ. Acad.
H. ELEVATA. — PI. 37, fig. 2. As in Journ. Acad. Synonym
H. Knosviliiana ? Fer. Tab. Syst. p. 33.

36

H. PROFUNDA. — Plate 37, fig. 3. As in Journ. Acad. My
description of this shell was published in the year 18^1. Lamark's
description of H. Richardi did not appear until April, 1822, but
he quotes, by anticipation Ferussac, Hist, des Mollusques, No. 174,
for the specific name, which was, however, not then published in
that work, but appeared in the Tableau Systematique of the latter
author in the earlier part of the same year. The name of pro-
funda has therefore the priority, and consequently must be
adopted.

No. 5.— August, 1832.
Helicina orbiculata. — Plate 46, f. 1, 2, 3. Same as Oligyra
orbiculata, Nicholson Encycl.

H. occulta. — PI. 40, f. 4, 5, 6. Same as Trans- Journ. Med.

No. 6.— April 1834. On the cover.

It seems probable that Helix irrorata is a variety of H.
lactea. Mull., with which I compared it when describing it.

Caracolla helicoides, Lea. — Trans. Am. Phil. Soc. vol. iv.
N. S., is variety a, of Helix palliata, Say, H. denotata, Fer.

Helix carolinensis, Ibid. — Corresponds by descriptions and
figures with H. appressa. Say, Var. a.

No- 5 and 6. — Descriptions of some new Terrestrial and
Fluviatile Shells of North America, &c.

Helix lucubrata. — Shell subglobose, depressed, reddish
brown, polished, subtranslucent ; whorls over four, much wrin-
kled ; spire much depressed, convex ; suture moderate ; beneath
paler 9 umbilicus open, rather large ; aperture nearly orbicular ;
labrum simple.

Greatest width one inch. Inhabits Mexico. Closely allied to
H. inornata. Nob., but the umbilicus is much larger, and the
aperture is mor« accurately rounded ; the color is nearly the same,
excepting that in the present it is of a deeper shade.

H. SUPPRESSA. — Shell subglobose, depressed, pale horn color,
poliihed, somewhat pellucid -, body whorl opake, whitish near the

37

aperture ; volutions six, wrinkled ; spire convex ; aperture sublu-
nate, narrower beneath ; within, a prominent tooth near the base,
distant from the margin ; labrum simple ; umbilicus rather small,
orbicular, profound ; region of the umbilicus indented.

Greatest breadth more than one-fifth of an inch. Inhabits
Pennsylvania.

I found a few specimens of this shell on the farm of my friend
Mr. Reuben Haines, at Germantown.

With the exception of the size and the armature of the throat,
it is somewhat of the habit of H. ligera, JVob.; but the opacity of
the body whorl near the aperture, is much more remarkable.
These characters, combined with that of the tooth, will readily
•distinguish this species from any other.

PoLYGYRA FATIGIATA. — Shell convcx beneath, nearly plane
above, the spire being hardly perceptibly elevated ; whorls a little
■over six, compressed, acutely carinated, crossed by numerous
raised, equidistant lines, which form grooves between them ;
superior surface not at all convex ; aperture subreniform ; labrum
reflected, regularly arctuated, describing two-thirds of a circle ;
within two-toothed, lower tooth conic obtuse, superior tooth com-
pressed, transverse, placed further within the aperture than the
inner one, from which it is separated by a wide and deep and
obvious sinus ; labrum with a very profound duplicature, which
has a concave surface, but with no emargination near its acute
tip ; beneath exhibiting only two volutions, without any distinct
groove on the external one near the suture ; beneath the carina
the elevated lines are obsolete.

Greatest breadth seven-twentieths of an inch.

Found by Mr. Lesueur in the vicinity of New Harmony. It is
very closely allied to that species which I described under the
name of plicata; the character of the mouth is very similar, but
in that shell, such is the situation and form of the teeth of the
labrum, that at first view they do not seem to be separated by a
remarkable sinus, and the inferior tooth is compressed and larger
than the other ; the duplicature of its labium is emarginate near
the tip. The present species is also larger, carinated, and the
•elevated lines are obsolete below the carina.

Helicina occulta. — Carinated ; carina almost concealed on
the spire, and nearly obsolete on the body whorl ; whorls about

38

five, carlnate, or with an acute shoulder, which is almost concealed
on the spire by the suture ; it becomes more obtuse and almost
obsolete, or even impressed on the body whorl, but near the
labrum it is again very obvious ; the whole surface has slightly
elevated, somewhat regular lines, forming grooves between them
across the whorls, and there is an appearance of revolving lines
on the body whorl, particularly beneath ; labrum entire, thick, a
little reflected, obtusely a little more prominent towards the base,
but not angulated.

All the specimens I have found are dead and bleached. They
occur abundantly in the ragged and abrupt " bluff,'' half a mile
below JNew Harmony, near the river bank, with many Helices that
are commonly found in the Western States. They are much of
the same size or even a little larger than the Helicina orbiculata,
Ao6., which species is destitute of carina or of prominent wrinkles
or elevated lines, its labrum is reflected, but not thickened, with
a distinct angle near its base.

Sl'CCINEA vermeta. — Shell suboval, yellowish, very thin and
fragile, somewhat diaphanous, with nearly three very oblique
volutions ; whorls very much rounded, wrinkled ; suture very
profoundly impressed ; spire rather prominent and acute ; aperture
ovate, the superior termination rounded.

Inhabits margins of ponds near New Harmony.

This species is remarkable for the very deep indentation of its
suture, giving to the whorls of the spire the appearance of being
almost separated from resting on each other ; and by this char-
acter it may be readily distinguished from the other species of this
country. It was found by Dr. Troost.

S. UNDULATA. — Shell suboval, pale yellowish, translucent,
fragile; volutions three and a half; spire moderate, wrinkles
obsolete, body whorl wrinkled, or rather slightly undulated:
columella narrowed, so as to exhibit the appearance of an interior
umbilicus, when viewed with a lens from the base.

Length about one-half inch. Inhabits Mexic >.

Very similar to S. ovalis, Nob., but the suture is not so deeply
indented, and it has from one-half to three-fourths of a whorl
more ; the surface of the body whorl also is rather undulated than
wrinkled. One of the individuals lived nearly twelve months in
my cabinet, without any apparent sustenance.

39

Pupa placida. — Shell dextral, cylindric-coiiic, pale yellowish
horn color ; apex whitish, obtuse ; whorls six and a half, some-
what wrinkled ; suture moderately impressed ; aperture unarmed,
longitudinally oval, truncate a little obliquely above by the
penultimate volution ; columella so recurved as almost to conceal
the umbilicus 5 labrum, with the exception of the superior portion,
appearing a little recurved when viewed in front, but when viewed
in profile, this recurvature is hardly perceptible ; umbilicus very
narrow.

Length over three-tenths of an inch. Inhabits Massachusetts.

For this shell I am indebted to Dr. T. W. Harris, of Milton,
from whom I have received many interesting species of our more
northern regions. At first view it might be mistaken for the P.
marginata, Jfob., but it is quadruple the size, and the labrum is
not reflected and thickened.

BuLiMUS ALTERNATUS. — Ovate conic, with alternate gray and
brownish longitudinal vittae. Inhabits Mexico.

Shell umbilicated, ovate-conic, with longitudinal lines, subequal,
gray and light brownish vittas ; the brown is paler, almost
approaching in some instances a drab ; the white vittse consists of
more or less confluent, transverse, irregular lines, and small spots ;
w^horls about six, a little convex ; suture not profoundly impressed \
labrum (in some specimens) with a thickened line or rib on the
inner submargin ; within white, with a perlaceous tinge.

Length one and one-fifth of an inch. Greatest breadth seven-
tenths. This species appears to be not uncommon in Mexico, as
many specimens were sent me by Mr. Maclure ; but from what
particular locality, I know not.

B. UNDATUS, Brug. — Occurs in some parts of Mexico. I
found a specimen on the road from Vera Cruz to the city. The
late Mr. Elliott, of Charleston, presented to me a Bulimus which I
described under the name of reses; but on comparing it to the
present species, I think it may be considered as a variety ; it is
rather less ventricose, the longitudinal lines are very slender and
pale, and the transverse lines much more distinct. It inhabits
trees on the south part of Florida.

B. SERPERASTRUS. — Elongate subovate, about six banded.
Inhabits Mexico. Shell conic or elongate subovate, umbilicated ;
whitish or white, with about six interrupted, more or less con-

40

fluent, dark rufous bands ; spire as long, or rather longer than
the aperture, with three or four widely interrupted bauds ; suture
not very deeply impressed ; whorls a little convex ; labrum widely
curved a little outwards ; columella rather wide at its origin.

Length one and a half inch ; greatest breadth, excepting the
lip, (parallel, of course, to the suture,) seven-tenths of an inch. I
obtained it on the side of the road between Vera Cruz and Mexico.

B. EMEUS. — With crowded, minute, transverse striae. Inhabits
Mexico. Shell conic or elongate ovate, slightly angulated on the
middle of the volutions, and covered with minute, undulated,
impressed, capillary lines ; whitish, with maculated bands : suture
not deeply impressed : aperture shorter than the spire ; labrum
exteriorly simple, interiorly with a thickened submargin ; colum-
ella short, recurved ; umbilicus small, but distinct ; spire with
the angulation concealed by the suture ; body whorl with the
angulation almost obsolete.

Length thirteen-twentieths of an inch ; greatest breadtb
(parallel to the suture) three-tenths. I found this species on the
road from Vera Cruz to Mexico. As I possess only the " Tableaux
Systematiques" of Ferussac's splendid work, the preceding species-
of Bulimus are offered with considerable hesitation ; but those
who possess that work can readily detect an error, if there be one.

Note. — Through the kindness of Dr. Meigs, the obliging
Librarian of the Academy, I have been able to hare impressions
taken of Mr. Say's plate of Helix clausa.

DESOHIPTIOISrS

OP

FLUVIATILE AND MARINE SHELLS

OP

NORTH AMERICA

BY

THOMAS SAY.

NEW YORK:
H. BAILLIERB, 290 BROADWAY.

LONDON :— H. BAILLIERE, 219 REGENT STREET.

PARIS : — J. B. BAILLIERE ET FILS, RUE HAUTEPETJILLE.

MADRID : — C. BAILLY-BAILLIERE, CALLE DEL PRINCIPE.

1858.

FLUYIATILE AND MARINE SHELLS

NORTH AMERICA.

[No. 1. The Article Conchology, from the tliird American edition of
Nicholson's Encyclopoedia, Philadelphia, 1819.*]

We here introduce descriptions, illustrated by figures, of a few
of the land and fresh water shells of the United States, induced
particularly by the silence with which these productions of our
country are regarded in the Systema Naturse. In the extensive
work of Lister, entitled " Historiae sive Synopsis Methodicae Con-
chynorum," &c., several of our shells are figured, and, to a few of
them, short descriptions are annexed, not, however, designated with
specific names ; of this work we have availed ourselves, from quo-
tations and references.

It will be readily perceived by the conchologist, that in the ar-
rangement we have deviated from the course pursued in this work
relative to the inviolability of the Linnaean system, so as to intro-
duce some of the more recent improvements in the construction of
genera, and that some considerable modifications are ventured to be
made in this article.

We think it proper to state, in addition to the above remarks,
which were annexed to the descriptions in the first and second
American editions of this work, that several species and three new
genera are now added, which, with the exceptions of a small num-
ber of new species now first published, we have previously given to
the world, in several detached essays, in the pages of the Journal
of the Academy of Natural Sciences, in the collection of which
Academy all the specimens are preserved.

*[The extracts are taken from the third edition. The previous editions
are referred to in the Index. — Ed.1

44

Grenus Planorbis. — Shell discoidal ; spire depressed, or con-
cave ; aperture oblique, rounded, broader than long, visible from
above, and emarginated by the convexity of the penultimate whorl ;
lips not reflected ; whorls lateral.

Animal aquatic, with two filiform tentacula, having the eyes
placed at the inner base ; operculum none.

Obs. The species for which this genus was constructed were
included by Linnaeus in his Genus Helix, The spire is sometimes
profoundly sunk, so much so as to be with difficulty distinguished
from the base.

Planorbis trivolvis. — Shell sinistral, pale yellow, brownish
or chestnut color, subcarinate above and beneath, particularly in
the young shell ; whorls three or four, striate across with fine,
raised^ equidistant, acute lines, forming grooves between them.
Spire concave ; aperture large, embracing a considerable portion of
the body whorl, within bluish white ; lip a little thickened in-
ternally, and of a red or brownish color, vaulted above ; umbilicus
large, exhibiting the volutions. Length one-fourth of an inch ■
breadth one-half of an inch.

Animal aquatic, dark ferruginous, with very numerous, confluent,
pale yellowish points; tentacula long, setaceous, with confluent
points ; foramen on the left side.

That ingenious naturalist, Mr. C. A. Lesueur, found this species
of a much larger size in French Creek, near Lake Erie ; breadth
three-fourths of an inch nearly ; color almost black, purplish red
within the mouth.

Cochlea, trium orhium. Lister. Conch, tab. 140. fig. 46.

Lister figures this shell pretty accurately, and it is referred to in
Gmelin's Edit, of Syst. Nat. p. 3615, as Albella, but it is certainly
not that species. Plate 2, fig. 2.

Planorbis bicarinatus. — Shell sinistral, pale yellow or brown-
ish, subcarinate above, and beneath translucent. Spire retusum-
bilicate, forming a cavity as deep as that of the base. Aperture
large, embracing a considerable portion of the body whorl, and
much vaulted above. Within red brown, with two white lines cor-
responding with the carina. Whorls three, wrinkled, and with
minute revolving lines. Length one-fourth of an inch ; breadth
nearly half an inch.

45

luhabitant aquatic, ferruginous, witli numerous yellowish dots ;
tentacula dotted and flexuous. Plate 1, fig. 4.

Eesembles the preceding species in its outline, but differs from
that shell in the remarkable unibilicate appearance of its spire ; it
is also destitute of those fine parallel raised lines, and is furnished
with minute striae, never visible in P. trivolvis ; the superior part
of the lip is more vaulted, and the carina more visible.

Planorbis parvus. — Shell horn color or blackish ; whorls
four, crossed by minute wrinkles ; concave above and beneath, and
equally exhibiting the volutions, body generally subcarinate on the
margin ; lip rounded, and not vaulted above nor thickened ; mouth
within bluish white. Breadth one-fifth of an inch.

Animal aquatic, brown, tentacula long, filiform, whitish, with a
darker central line, tail rounded.

Probably the same species with that figured by Lister, tab. 139,
fig. 45 ; it is very numerous in the Delaware, in company with the
two preceding shells. Plate 1, fig. 5.

Grenus Lymn^a. — Shell subovate, oblong, or somewhat taper-
ing. Aperture entire, longitudinally oblong, the right lip joined
to the left at the base, and folding back on the pillar.

Obs. These shells, as well as those of the preceding genus,
were placed by Linnaeus with his Helices, but they ofier charac-
ters sufficiently distinct, particularly their inhabitants.

Lymn^a catascopium. — Shell thin, horn color, red or black-
ish ; whorls foiu- or five, the first large, and generally the remainder
darker and rapidly decreasing to an acute apex, and wrinkled
across ; apertui'e large, oval, not three-fourths the length of the
shell. Length seven-tenths of an inch, breadth nearly one-half of
an inch.

Inhabitant yellowish, sprinkled with small, often confluent, paler
dots ; tentacula two, broad, pyramidal ; eyes black, placed at the
base of the tentacula ; tail obtuse, rounded or emarginate, not so
long as its shell. Plate 2, fig. 3.

It is with much hesitation that we adopt a new specific name for
this shell, having always heretofore considered it as the same with
the L. putris of authors, (which has been, perhaps, mistaken for
the Helix limosa of Linne.) As far as we can ascertain, the princi-
pal difference appears to be in the more oblique revolution of the

46

whorls in the European species, and the more abrupt termination
of the spire.

Inhabits the Delaware river and many other waters of the United
States, in considerable numbers, and may be found plentifully,
during the recess of the tide, about the small streams through which
the marshy grounds are drained, in company with several other
shells. When kept in a vessel of water, like others of its kind, it
will proceed not only up the sides of its prison, but also along the
surface of the water, the shell downward, with regularity of motion
and apparent ease. In this case the reverted base of the animal is
concave ; and as the surface of the water is compelled to a corres-
ponding concavity, the pressure of the atmospheric column will ac-
count for the sustentatiou of the animal (whose specific gravity is
much greater than that of the water) in this singular position. It
occasionally crawls to the margin of the water to inhale a supply of
air; with this object the foramen is protruded to the surface, and
opened with an audible snapping sound, similar to that produced
by the resilience of the nib of a pen.

There is a species of this genus that we have named Lymn^a
JUGULARis ; and which, in consequence of its having been found
but once, must be considered as a doubtful inhabitant of the United
States. It may be thus described. Shell tapering ; whorls about
six ; suture not deeply impressed ; aperture hardly equal to half
the length of the shell, but little dilated ; within brownish, particu-
larly upon the column, which is contracted in the middle ; outer
lip white, and almost imperceptibly repand within ; umbilicus very
distinct. Length one inch.

A specimen was also brought from the West Indies by Mr.
L'Hermenier of Charleston.

LYMNiEA HETEUOSTROPHA. — Shell sinistral, subovated ; color,
pale yellow, chestnut or blackish ; whorls four, the first large, the
others very small, terminating rather abruptly in an acute apex 3
aperture large, somewhat oval, three-fourths of the length of the
shell, or rather more ; within of a pearly lustre, often blackish :
lip a little thickened on the inside, and tinged with dull red.

Inhabits with the first species, and almost as numerous. Plate
l,fig.6.

Animal resembles that of L. catascoplum, but is of a darker
color and longer than its shell, the tentacula also are longer, and
setaceous ; tail acute.

47

The mantle is trifid at the base of the pillar lip, and at the upper
corner of the aperture ; deposits eggs the beginning of May ; eggs
enveloped by a transparent gelatinous substance ; the nucleus, after
a few days, appears of a pale or milk white color, and not so well
defined as those of L. catascopmm.

Paludina subcarinata* — Shell with three whorls, which
are rounded, and subcarinated, reticulated with striae and wrinkles,
sometimes without the striae ; suture deeply impressed ; apex trun-
cated and re-entering ; aperture more than half of the length of the
shell, oval ; elevated lines or subcarina on the body two, three, and
sometimes none. Length half of an inch ; breadth foui'-tenths.

Inhabits with the preceding species. Plate 1, fig. 7.

Animal viviparous, with a chestnut, coriaceous operculum, white,
spotted with orange ; head pale orange, not extending beyond the
shell ; tentacula darker, short, subulate ; eyes situated at their base,
elevated, black and conspicuous ; base of the animal much ad-
vanced, broad, truncate, purplish before, tail rounded behind.

Paludina Virginica.* — Shell tapering, olive, horn color or
blackish, under the epidermis tinged with green ; whorls seven?
but little rounded, crossed by curved wrinkles on the spire, and re-
clivate ones on the body ; a dull red line revolves near the base of
the whorls, and on the middle of the body a reddish-black broader
line, from within the upper angle of the aperture, runs parallel vrith
the other, and terminates near the base. Aperture subovate, more
than one-third as long as the shell, lip not thickened, but dilated
at the base. Length one inch; breadth two-fifths of an inch.
Plate 2, fig. 4.

Lister's Conch, tab. 117, /r/. 7. The basilar part of the lip in
Lister's figure is deficient.

Inhabitant bluish-white beneath, with orange clouds each side
of the mouth ; above pale orange, shaded with dusky and banded
with numerous black interrupted lines ; mouth advanced into a,
rostrum as long as the tentacula, which are darker at the base, and
setaceous ; base of the animal with an undulated outline.

It often occurs in our rivers, and is readily discoverable in clear
water, by the channel it forms in the mud.

*[In the earlier editions of Nich. Enc. this species was described under
Lymnaea. — Ed.]

48

Specimens of tliis shell, brought from the Lakes and their vicin-
ity, by Mr. Lesueur, had the revolving lines very obscure or obso-
lete.

Lister's lower figure of tab. 109 also resembles tliis shell.

Paludina vivipara.* — Shell subconic, with six rounded
whorls ; suture impressed, color olivaceous or pale, with three red-
brown bands, of which the middle one is generally smallest ; whorls
of the spire with but two, aperture suborbicular, more than half
the length of the shell. Plate 2, fig. 3.

Donov. Brit. Shells, tab. 87, Helix vivipara.

Lister. ConcJi. tab. 126, Jig. 26; Cochlese vivipara fasdata.

It is doubtful whether or not this is the same as the vivipara,
but it certainly approaches very near to it; we, however, refer it to
that species until a specific diflPerence can be indicated, which at
present we are unable to do ; the spire of this species is rather
more obtuse, and the suture not so deeply impressed, as in the figures
of the European specimens above mentioned.

Paludina dissimilis. — Shell conic, dark horn color or black-
ish ; whorls about three, with obsolete, distant wrinkles, and an
abrupt, acute, prominent carinated line, which revolves on the mid-
dle of the body whorl, and is concealed on the spire by the suture;
suture not indented, aperture oval, half as long as the shell, within
sanguineous beneath the carina, and at base and apex ; columella
emarginated, a little flattened at the base. Length about two-fifths
of an inch.

Var. a. Carina obsolete on the ventral portion of the body
whorl.

Var. 6. Carina distinct on the spiral whorls, owing to their more
oblique revolution.

The surface of the whorls of the spires is generally covered with
inequal calcareous matter, resembling a fortuitous accumulation of
mud or earth on that part, but which appears to be superposed by
the animal, probably with the intention of retaining a proper specific
gravity. The apex is often tnuicated.

This species was found by Mr. Thomas Nuttall, during a journey
to Pittsburg.

*[In the earlier editions of Nich. Enc. this species was described under
Lymnaea. — Ed.]

49

Paludina decisa. — Shell subconic, olivaceous, truncated at
the apex ; whorls four, wrinkled across and banded with minute
distant striae.; terminal whorl very short; suture impressed and
conspicuous ; aperture subovate, more than half of the length of
the shell, entire ; within bluish white. Operculum coriaceous,
elevated on the disk and concentrically striated. Length one inch ;
breadth three-fourths. Plate 2, fig. 6.

Cochlea virginiana 4 fiava vin'descens, non fasciata. Lister,
Condi, tab. 127, Jig. 27.

The young shell resembles L. mhcarinata, but the whorls are des-
titute of an elevated line, the suture is not so deeply impressed,
and the aperture is narrower above.

Animal with the foot larger, suddenly a little dilated each side
before and truncate in front, widely ; foot livid, thickly maculated
with irregular orange spots, which are much smaller beneath ; head
and tentacula spotted with orange ; eyes on a prominent angle, at
the external base of the tentacula.

I found the animal viviparous in October ; the young shell had
then three complete whorls, which were spirally striated.

Grenus Unio. — Shell transverse ; with three deeply impressed
cicatrices ; hinge with a strong irregular tooth, and anterior lamel-
lifonn, elongated one in one valve, inserted between two corres-
ponding teeth and laminae of the other.

Ohs. The shells of this genus inhabit fresh water ; they were
placed by Linnaeus with the Mj/se, fi'om which they diifer in verj-
essential particulars ; as is obvious from the number, situation, and
figure of the teeth, and the organization and habits of the included
animal.

Unio crassus. — Shell varying in form and surface ; remarka-
bly thick and ponderous ; epidermis horn-color, diiferent shades of
brown or black ; beaks carious, often much eroded, pure perlaceous,
or silvery white, more prominent as the shell approaches an orbicu-
lar form ; primary teeth, not very oblique. The dimensions of
three specimens were as follows :

Length, 3 inches; breadth, 4 2
2 " " 4i

2 " "2

Plate 1, fig. 8.
Musculis brevoir, admodum crassus, ex interna parte subrosens.

50

car dine incisuris mnmlis exasperate . Lister, Conch, tab. 150,
Jig. 5.

Unc7/c. Method, vol 63, tab. 249, Jig. 1.

By these dimensions it will appear to vary veiy considerably, beiag
a regular oval ; mucli elongated ; ovate or nearly orbicular ; sone-
times with two or three longitudinal or oblique waves ; rarely tuler-
culate; within perlaceous or red purple; teeth very thick, crenaied,
and resembling those of the next species. It is very probable that
we have here included several distinct species, but at present we
are not sufficiently well acquainted with the inhabitants to separate
them. Gmelin refers to Lister's figure for his Mytillus a/gneus,
but we can discover no resemblance between them.

Found plentifully in the river Ohio and its tributary streams.
Unio plicata. — Shell suboval, thick and ponderous; valves
with two three more conspicuous undulations, which are profound,
very oblique, continued to the anterior basal edge, and not arising
from the umbo ; umbo decorticated, sometimes much eroded ;
within perlaceous, distinctly impressed by the undulations.

This species may be distinguished from any of the numerous
varieties of the preceding species by the oblique direction of the
undulations, of which those nearest the base are largest, and seem
to originate behind the beaks.

It was found by Mr. Lesueur in Lake Erie, and was communicated
by him under the above name.

Unio purpureus. — Shell suboval, somewhat compressed, with
smaller wrinkles placed between larger ones, color dark brown ;
beaks placed nearer one end, very carious, not prominent, generally
the epidermis and pearly strata are removed, exhibiting a wax-yel-
low ground ; within reddish purple, varied with green, no cavity
under the beak; teeth resemble the preceding. Length, one inch
and five-eighths; breadth, two inches and four-fifths. Plate 3,
figl-

This species is more numerous in the rivers Delaware and Schuyl-
kill than any other of the genus : in the rivers of the Southern
States it arrives at a more considerable magnitude, measuring some-
times four inches, or more, in breadth. These large specimens,
and sometimes the smaller ones, arc a little shortened on the base
opposite to thd lamellar teeth.

Unio ovatus. — Shell subovate, convex, not remarkably thick,

51

horn color, not radiated ; flattened and fuscous on the anterior mai-
gin ; beaks decorticated, placed nearer central ; umbo prominent ;
within parlaceous ; cavity of the beaks capacious; primary teeth
very oblique, almost parallel to the posterior margin and much
compressed. Length, three inches; breadth, four inches.

Inhabits the Ohio river and its tributary streams.

Eiicyc. Method, vol. 63, tab. 24:S, Jig. 5. Plate 2, fig. 7.

Unio cariosus. — Shell moderately thick, much longer before,
and shorter behind the beaks ; olive green, sometimes radiate with
green, and with fine interrupted wrinkles placed in longitudinal
rows, but usually the green radii are wanting, or only visible in the
anterior margin, and the wrinkled radii indistinct ; in older shells
the naiddle of the base is a little shortened ; beaks somewhat promi-
nent, rather distant, carious, exposing a wax-yellow surface ; con-
cavity bluish-white, teeth resembling those of the preceding species,
but the primary ones are not so much compressed or oblique ; they
are often sub-conic and crenate. Length one inch and a half :
breadth, two and a quarter. Plate 3, fig. 2.

Muscvlus latioVj sub/uscus, Cseruleis lineis Radiatus. Lister,
Conch, tab. \b2,fig. 7.

Martini's figure of U. jiictorum resembles this shell in outline.
Vol. 6.

Vei-y common in the Delaware and Schuylkill rivers.

Gmelin, Ed. Syst. Nat. p. 3220, refers to Lister's figure as a
variety of Mya radiata, a native of Malabar : but we have ventured
to consider it a distinct species ; the largest we have seen was
brought from Wilkesbarre by Mr. Lard. Vanuxem, in length two
and one-fourth, breadth three and three-fourths inches. The animal
rarely infested by a parasite. See the article Ht/drachne.

Unio ochraceus. — Shell thin, fragile, translucent, subovate,
hinge margin somewhat rectilinear, color from a pale reddish orange
to a pale olive ; generally radiate with dull green and with minute
wrinkled radii; anterior margin very finely wrinkled; beaks de-
corticated and approximate, with two or three small concentric un-
dulations ; within bluish-white or ochraceous, tinged with red near
the base ; teeth very oblique and much compressed. Length one
inch and a quarter : breath, one and three-quarters. Plate 2,
fig. 8. •

This shell; in many respects, resembles the preceding, with which

52

it is found, but is not so obtuse in front, and is much less rounded
at the hinge margin it is also much thinner, and the beaks ap-
proach each other more closely.

Unio nasutus. — Shell thin, oblong, compressed, rostrated, horn
color or fuscous, with fine crowded wrinkles obscurely radiate with
green ; within bluish-white ; beak cavity hardly any ; teeth crenate.
Length, one inch and one-eighth : breadth, two and three-fifths.

Very common in the Delaware and Schuylkill. Plate 4, fig. 1.

Musculus fusctcs, augustior, exaltera parte Cuneatim protensiis.
Lister, Conch, tab. 151, Jig. 6.

Unio alatus. — Shell moderately thick, sub-triangular, gener-
ally gaping at the posterior part of the base, fuscous, wrinkled ;
beaks not prominent, placed very far back and decorticated ; base
almost rectilinear ; hinge margin remarkably oblique, rising near
the termination of the cartilage into an alated projection, and form-
ing almost a right angle with the inferior slope, which is nearly
equal in length ; within red-purple, often with numerous tubercles,
which, upon the gaping limb, are confluent ; cicatri(?es very rough ;
teeth crenate, the external laminated one obsolete, only one in each
valve being very perceptible. Length, including the projection,
three inches and four-fifths ; breadth, five inches and a half. Plate
4, fig. 2.

Bnc9/c. Meth. vol. 63, tab. 248, /f/. 1, a, b?

Mr. Lesueur found this species in Lake Erie, very thin and
fragile.

The specimen from which this description is taken, and also the
next species, were purchased by Mr. Joseph Watson, at the sale of
the late Professor Barton's collection, and by him presented to the
Academy of Natural Sciences of Philadelphia. There is also a
specimen in the Museum of Mr. Peale.

Unio cylindrtcus. — Shell very thick, sub-cylindrical, emargin-
ate before, pale horn-color varied with greenish ; hinge margin
undulated obliquely across the wrinkles, rough on each side, rec-
tilinear and parallel to the base ; beaks broad and prominent, with
a deeply impressed posterior lunule ; within porlaceous, teeth thick
and crenate ; cavity of the beaks very deep. Length, one inch
and three-tenths ; breadth, three inches and one-fifth. Plate 4,
fiff. 3.

53

From the collection of the late Professor Barton ; it is said to be
found in the river Wabash.

Unio undulata. — Shell thin, convex, suboval, greenish or
olivaceous, with obtuse concentric wrinkles and radiate with green,
a little uneven before ; beaks prominent, acute, approximate, decor-
ticated, and with four or five large obtuse, distant undulations, dis-
appearing towards the basal margin ; within bluish-white, cavity
deep ; teeth one in each valve, think and strong ; that of the left
valve crenated, of the right valve somewhat bifid, and gradually
sloping to the hinge margin. Length, three-fifths of an inch :
breadth, nine-tenths of an inch. Plate 3, fig. 3.

Found in the Delaware and Schuylkill rivers, but is rather rare,
and resembles Anodonta undulata.

This genus, in conjunction with Dlpas of Leach, will complete
the chain of connection between the two genera Unio and Ano-
donta. It corresponds with these genera, in the number of its
cicatrices, but is separable from Anodonta, by its primary tooth ;
from Unio by being destitute of the lamelliform teeth ; and from
Dipsas, also, by the last mentioned character, as well as by the
presence of a primary tooth, which is wanting in that genus.

This new genus we proposed in the former editions of this work,
when describing the Undulata, under the name of Monodonta ;
but as the same term has been applied to a genus of univalves, I
have substituted that of Alasmodonta.

Genus Anodonta. — Shell transverse, with three obsolete mus-
cular impressions ; hinge simple, destitute of teeth.

Obs. The shells which constitute this genus were arranged by
Linnaeus and many other writers, under the genus Mytillus.

Anodonta cataracta. — Shell thin, fragile, translucent, ob-
long-oval, convex, covered with a green olive, radiated, epidermis,
within perlaceous; beaks nearer central, frontal margin brown.
Length, two inches and two-fifths : breadth, four inches and a half
concavity of one valve nearly.seven-eighths of an inch. Plate 3,
fig. 4.

This large muscle occurs in lakes, milldams, &c., and bears some
resemblance to the A. anatinus, of Europe.

Found by Mr. I. Lukens, in the deep part of a mill-dam.

Anodonta marginata. — Shell very thin, fragile, somewhat

54

compressed, translucent, subovate; epidermis green olive, paler
on the disk and greener before ; anterior margin fuscous ; beaks
nearer the posterior end ; within bluish-white, edged with whitish.
Length, one inch and a half; breadth two inches. Plate 3, fig. 3.

Resembles the preceding, but is more ovate, and the beaks are
placed much further back ; it is very common in our rivers.

Anodonta undulata. — Shell thin, fragile, convex, olivaceous,
obscurely radiate and obtusely wrinkled ; umbo prominent, decor-
ticated, with four or five obtuse undulations divsappearing on the
disk. In the right valve, immediately under the beak, the margin
is curved inwards for the reception of a coiTesponding marginal
projection of the opposite valve. Length, nearly half an inch j
breadth, nearly seven-tenths of an inch. Plate 3, fig. 6.

This species is perhaps rare ; it does not exactly agree in all its
characters with the genus, but approaches nearer it than to any
other ; it resembles Alasviodonta tmdulata, for the young of which
it might readily be mistaken.

Genus Cyclas. — Shell almost orbicular, or a little transverse,
without fold on the anterior margin ; two or three primary teeth,
and lateral, remote, lamelliform ones on each side.

Obs. The shells of which this genus is composed were formerly
placed with the Cardia and TelUnse ; to the former they are more
closely allied ; it was originally established by Seopoli under the
name of Sphserhmi, this was changed by Lamarck to Cyclas, which
is now adopted by Latreille and other wi'iters, notwithstanding the
previous application of the term to a genus of plants.

Cyclas similis. — Shell suborbicular convex, base a little flat-
tened, with nearly equidistant, raised, concentric lines, giving a
slightly sulcated appearance to the surface, and generally a more
conspicuous elevated darker wave, marking the former year's growth
of the shell. Epidermis brown or ferruginous ; beak nearer cen-
tral and obtuse ; hinge with minute very oblique teeth, lateral ones
very distinct, elongated, and considerably resembling those of the
next species. Length, seven-twentieths of an inch ; breadth, two-
fifths : a specimen measured in length nearly three-fifths of an inch.
Plate 1, fig. 9.

A'ery much resembles Tellina cornea of authors; is found in
plenty in the river Delaware ; animal viviparous ; from one speci-

55

men three pale yellow active young ones were taken, the largest
of which measured in breadth three-twentieths of an inch in the
month of May.

Cylas DuniA. — Shell oblique, subovate convex, concentrically
wrinkled, veiy pale horn color or whitish, with sometimes a darker,
but not raised band, marking the preceding year's growth of the
shell ; beaks placed much nearer one end ; within whitish, primary
teeth very distinct, in one valve two divaricating ones, in the other
but one; exterior laminal tooth very small. Length, five-twentieths
of an inch ; breadth, three-tenths. Plate 1, fig. 10.

Inhabits the river Delaware in company with C. similis, and very
much resembles TelUna amnica of authors.

The shells here described are in the collection of the Academy
of Natural Sciences of Philadelphia.

It was originally the intention of the writer of this article to
insert here, not only descriptions of the fresh water and land shells,
but those of the coast also ; finding, however, that the descriptions
of the latter were by far too voluminous to be comprised within the
space allotted to this article, and that they had more generally
found a place in the systems, the design is, with respect to this
work, necessarily relinquished. To all the species here described,
with the exception of three or four, we have been constrained to
adapt specific names ; but should it appear that we have been anti-
cipated by the labors of some recent conchologist, whose wi'itings
we have no opportunity to consult, we shall readily bow to the
right of priority, which ought unquestionably to be on all occasions
imperative and exclusive.

The primary divisions of the Linnjean system, in the latest
edition of the " Systema Naturae," as before observed, consist of
three orders, Multivale, Bivalve, and Univalve, each of which is
subdivided into genera. The Multivalves contain the Chiton,
Leapas and Pholas ; the Bivalves, Mya, Solon, Tellina, Cardium,
Mactra, Donax, Venus, Spondylus, Chama, Area, Ostrea, Anomia,
Mytillus, and Pinna ; and the 'Univalves, Argonauta, Nautilus,
Conus, Cypraea, Bulla, Voluta, Buccinum, Strombus, Murex, Tro-
chus. Helix, Nerita, Haliotis, Patella, Dentalium, Serpula, Teredo,
and Sabella. Which see. See also Shells.

[In the earlier editions of Nich. Enc. the following genera and species
were not described : as the descriptions were only copied into the third

56

edition, from the Proc. Acad. Nat. Sci., I will not repeat them here. See

Index. — ^Ed.]

Planorbis glabratus, Paludina,

lymn.a:a columella, " limosa,

CyCLOSTEJIA, ' ' LAPIDARLA.,

' ' TKICARINATA, AlASMODOSTA,

AnCTLUS, " MAKGINATA,

'♦ RrvuLAEis, Cyrena,

CyRENA CAROLnOENSIS, Bosc.

[No. 2. From the Philosophical Transactions of the Royal Society,
1819, p. 107.]

On the Genus OCYTHOE ; beiiiff an extract of a letter from

Thonias Say, Esq., of PMladelpTiia, to Wm. Elford Leach,

M. D., F. R. S.

I have before me a specimen of Ocythoe in an Argonauta, form-
ing part of the collection of the Acad. Nat. Sciences. It was
taken from the stomach of a dolphin, which was caught in sound-
ings on our Atlantic coast, and is in the most perfect state of pre-
servation, not having suffered the slightest decomposition from
gastric action.

It is sufficiently distinct from your 0. Cranchn, as well as from
the animal of Naiitihis sulcatus of Klein ; and if the figure given
by Shaw of the animal of Argonauta argo has any pretensions
to accuracy, it is most probably an unknown species.

I here attempt a description of it, and also submit a few remarks
on the genus :

Ocythoe punctata. — Body pale, punctured with purplish;
abdomen conic-compressed, vertical, semifasciate near the sum-
mit, with a profoundly indented transverse line ; arms much longer
than the body, attenuated, filiform at their tips, alated ; membranes
rounded.

Inhabits the Atlantic Ocean near the North American coast.

Descrij). Abdomen conical, slightly compressed, nearly vertical
with respect to the disk of the head, with a profoundly indented
transverse line, which extends half round, near the summit. Arms
attenuated, much longer than the body, filiform towards the tip,
slightly varied with brassy, inferior ones when extended double
the length of the body; suckers alternate, becoming gradually
smaller towards the extremities of the arms, where they are very

57

minute ; membranes of the anterior arms rounded or suborbicular,
extending half way to the base of the arms ; periphery occupied
by the attenuated portion of the arm, which near its extremity
passes upon the disk of the membrane, and terminates abruptly
near the base of the expansion ; the membrane is carinately de-
cun-ent on the inferior surfoce of the arm near the base of which
it terminates ; the inferior surface of the membrane is brassy, and
more numerously maculated than the superior, which is pale.
Length from the disk to the tip of the abdomen 2 inches.
Length of the abdomen 1? "

Greatest breadth of abdomen 1 '|io "

Length of the alated arms / 2| "

Length of those of the opposite side 5 "

Eggs subovate, attached to a delicate pedicle by a small basilar
tubercle. These fill the involuted spire in the specimen, besides a
considerable portion of the body of the shell.

The suckers are very like those of 0. CrancJm, but the arms
are much more elongated, and the abdomen longitudinal with
respect to the head. This animal seems not to be unfrequently
the prey of some of the larger fishes, for in addition to the in-
stance above mentioned, Bose informs us that in his passage between
Europe and America, he found a specimen in the stomach of a
Cm-phsena equiselis, Grmel., but very much decomposed j and in
the musevma of Mr. Peale, in this city, a fine Argonauta occurs,
which was taked from the stomach of a shark.

With respect to the contested question relative to the parasitic
nature of the animals of this genus, I believe the remark will hold
good generally, if not absolutely, that those molluscous animals
that form the shell in which they reside, are more or less connected
with it by muscular or membranaceous attachment, or by the per-
manent spiral form of the posterior part of the body ; and that the
body of the animal complies with the inequalities of the chamber
of the shell, or rather that the shell is moulded upon the body, so
as to be in contact with it in every part. So careful are they to
fill the cavity to its very summit, that when from their increase of
growth, the apex of the shell is vacated in consequence of its
straightness, either that part is removed by the animal, and ad-
ditional calcareoas matter is secreted to close the aperture thus
formed, or it is permitted to remain and the cavity is filled up by

7

68

the same secretion ; of the former process we have an instance in
Bulimus drcollata ; and of the latter, many instances occur, familiar
to the knowledge of conchologists. The Ocytlioe offers to onr
consideration a remote deviation from these ordinary laws which
apply to the testaceous mollusca, inasmuch as it only resides in the
last volution or hody of the shell. In the specimen ahove de-
scribed, the sides of the abdomen are slightly canaliculated, in con-
formity with the sculpture of the inner lateral surface of the shell ;
but it is worthy of remark, that the portion which corresponds with
the most unequal part of the chamber, the carina, is not at all in-
dented ; which fact induces the supposition that the shell does not
fit the body, and of course was not made for it, otherwise it does
not seem probable that the body would be remote from the shell
in one part, and impressed with its asperities in another.

Such also is the form of the inferior part of the abdomen, that
it never could have revolved in the cavity of the involuted spire ;
yet we have never been informed that the vacated spire has been
either broken or solidified. Neither is there any attachment what-
ever between any part of the body and the including shell, by an
organ appropriated to that office. In consequence of this organ-
ization the Ocytlioe, cannot adapt itself to the form of the cavity
in which it rests, or secure itself there so completely as the well
known parasitic Paguri are enabled to do, in consequence of the
pliability of their vesicular abdomen, and by the agency of their
terminal hooks or holders. Such observations seem to afford pre-
sumptive evidence of the parasitic nature of these animals.

It does not appear to me probable that the Ocytlio'i ascends to
the surface of the water by exhausting its shell of the included
water ; for if this were the fact, those females, whose shell is in
great part filled with eggs, could not visit the surfiice. But the
change of specific gravity is doubtless effected in its own body, by
which it is enabled to sustain itself on the surface at will, or to
descend to the bottom promptly at the approach of danger.

The shells which in stnicturc and appearance approach nearest
to Argmimita are unquestionably to be found in the Pteropoda ;
and the examination of Carinaria, Atlanta, and Spimtdla, woxdd
almost lead us to suppose that the artificer of Argonauta is in
reality of that division ; but if this supposition be indicated by
the conformation of the shell, it does not seem to be corroborated

59

by the probable habits of the animal. All those hitherto discovered
of that group, arc known to swim at the surface of the ocean, and
not being furnished with other organs of locomotion than fins, they
cannot glide upon the bottom ; we must, therefore, (analogically)
suppose this to have been the habit of the animal ; and yet it is
hardly admissible that it should, in that case, have eluded the
observation of voyagers, since the shell has not unfrequently been
found in a state of occupancy by the parasite.

[No. 3, Journal of the Academy of Natural Sciences of Philadelphia.]

[J. A. N, S. vol. i. p. 13, et seqq. May, 1817.]

Grenus Cyclostoma. — A subdiscoidal or conic univalve. The
aperture orbicular, with a circularly continued margin, often sud-
denly and widely reflected.

Cyclostoma tricarinata. — Shell with three volutions ; three
revolving, carinate, prominent lines, giving to the whorls a quad-
rate, instead of a cylindric appearance. Suture canaliculate, in
consequence of the whorls revolving below the second carina and
leaving an interval. Spire convex, apex obtuse. Umbilicus large.
Carina placed, one on the upper edge of the whorl, one on the
lower edge, and the third on the base beneath. Breadth one-fifth
of an inch.

Inhabits the river Delaware. Rare. Found by Mr. Le Sueur,
whose proposed name is here adopted.

Cylostoma lapidaria. — Shell turreted, subumbilicate, with
six volutions, which are obsoletely w^rinkled across. Suture im-
pressed. Aperture longitudinally ovate-orbicular, operculated,
rather more than one-third of the length of the shell.

Length about one-fifth of an inch. Collection of the Academy
of Natural Sciences. •

Inhabitant not so long as the shell, pale ; head elongated into a
rostrimi as long as the tentacula, and emarginate at tip ; tentacula
two, filiform, acuminated at tip, short ; eyes prominent, situated at
the external or posterior base of the tentacula; base or foot of the
animal dilated, oval, obtuse before and behind.

Found under stones, &e. in moist situations, on the margins of
rivers. Like those of the genera Lymnxa and Planorbis this

60

animal possesses the faculty of crawling on the surface of the water,
in a reversed position, the shell downward.

Geuus Lymn^A. — Shells subovate, oblong or somewhat taper-
ing. Aperture entire, longitudinally oblong, the right lip circu-
larly joined to the left at the base and folded back on the pillar.

Lymn^a columella. — Shell thin, fragile, hom-color ; whorls
four, longitudinally wrinkled. Spire prominent, acute. Suture
not much impressed. Aperture dilated, ovate. Columella much
narrowed near the base, so that the view may be extended from the
base almost to the interior apex of the shell. Length seven-tenths
of an inch nearly; of the spire one-quarter of an inch.

Inhabits stagnant waters and miry places. Collection of the
Academy.

Animal aquatic, base not so long as the aperture ; dusky, with
small whitish spots ; tentacula broad, pyramidal, compressed ; eyes
small, black, placed at the inner base of the tentacula.

This species is allied to L. catascopium of the American edition
of Nicholson's Encyclopedia, but the revolution of the whorls is
more oblique, the shell thinner, the aperture much more dilated,
and the columella differently formed. For several specimens of
this shell I am indebted to Mr. Titian Peale.

[J. A. N. S. vol. i. p. 124, et seqq., Oct., 1817.]

Genus Ancylus. — Shell conic, not spiral, concave beneath,
above with a simple apex. Animal with the eyes placed at the
inner base of the tentacula.

Ohs. This genus has been by writers confounded with the
PatettFC. The European species are Patella lacnstris andjluviatt-
lis of Linn6.

Ancylus rivularis. — Shell corneous, opake, conic-depressed,
apex obtuse, nearer to, and leaning towards, one side and one end ;
aperture oval, rather narrower at one end, entire ; within milk-
white.

Length one-fourth of an inch. Cabinet of the Academy.

Common, adhering to stones in rivulets ; the animal resembles
the inhabitant of shells of the genus Lynvnsea, the tail is veiy ob-
tuse, rounded.

61

Grenus Paludina. — Shell subovate, operculated ; aperture en-
tire, longitudinally ovate, narrowed above ; lip simple, not dilated
or reflected.

Ohs. This genus has been very lately separated by Mr. La-
marck from the Q/cIostomx, with which it corresponds, except in
having no diluted lip, and the aperture is angulated above. The
animal has a short rostrum, two acute tentacula with eyes at their
external base, a small membranaceous wing each side of the body
before, foot double before, the wing of the right side is folded int^>
a small canal, by which the water is introduced into the respiratory
canal. Latr. To this genus will be referred several of the
Lymnse,a of the American Edition of Nicholson's Encyclopaedia
as L. decisUf vivipara and subcarinata.

Paludina limosa. — Shell conic, subumbilicate, dark horn
colored, generally incrusted with a blackish irregular covering on
the spire, and sometimes on the body, which completely obscures
the obsoletely wrinkled epidermis ; aperture ovate-orbicular ; suture
impressed.

Length three-twentieths, breadth one-teuth, of an inch. Cabi-
net of the Academy.

Animal whitish ; head brown ; mouth, tentacula, orbits, and vitta
on each side of the neck, white ; tentacula filiform, more than half
as long as the base of the animal ; rostrum about half as long as
the tentacula, annulate with darker lines above ; foot white,
brownish above, short, suboval, truncated before, and rounded
behind.

Extremely numerous on the muddy shores of the rivers Dela-
ware and Schuylkill, between high and low water marks.

[J. A. N. S. vol. i. p. 280, June, 1818.]

Planorbis glabratus. — Shell sinistral; whorls about five,
glabrous or obsoletely rugose, polished, destitute of any appearance
of carina ; spire perfectly regular, a little concave ; umbilicus large,
regularly and deeply concave, exhibiting all the volutions to the
summit ; aperture declining, remarkably oblique with respect to
the transverse diameter.

Breadth nearly nine-tenths of an inch. Inhabits South Caro-
li na. Cabinet of the Academy.

62

Presented to the Academy by Mr. L'Hermenier of Chai-leston,
am intelligent and zealous naturalist ; he assured me that this species
inhabits near Charleston. It somewhat resembles large specimens
of the P. trivolvis of the American edition of Nicholson's Encyc.^
but differs in the total absence of carina, and in having a more
smooth and polished surface, as well as a declining and more
obliqvie aperture, and a more profound and much- more regularly
concave umbilicus.

[J. A. N. S. vol. i. p. 459, 4G0, Dec, 1818.]

Genus Alasmidonta. — Shell transverse, equivalve ; inequila-
teral, hinge with a primary tooth in each valve ; cicatrices three.
Animal resembling that of Unio ?

Alasmidonta marginata. — Shell transversely oblong-suboval,
white, covered with an olive brown epidermis, obsoletely radiate
with green numerous concentric wrinkles ; umbo, with about three
concentric undulations ; ligament slope abruptly depressed, with
numerous, obtuse, oblique rugae, decussating the concentric ones,
which are obsolete in that part ; within bluish-white, margin white ;
cavity of the umbo not distinctly impressed by the external undu-
lations ; tooth compressed, oblique, nearly parallel with the poste-
rior slope, and terminating abruptly behind.

Length, exclusive of the umbo, one inch and a quarter, breadth
two inches and a half. Cabinet of the Academy*

The inner margin is of a chalky whiteness, in this respect re-
.sembling Anadonta mar(jinata. It was communicated to me by
Mr. Isaac Lea, who found it in the Scioto river.

Unio tmdulata of the first and second American editions of
Nicholson's Encyclopi^dia, is a species of this genus, but it is very
distinct from the marginata.

This genus will be properly placed between Un!o-A\\^ Aiiodonta,
and in conjunction with Dispas of Leach, it will complete the
chain of connection between those two genera. Alasmidonta
coiTCsponds with those genera in the number of its cicatrices, but
is separable from Anodonta by its primary tooth ; from Unio by
being destitute of the lamelliform teeth ; and from Diapas also by
the last mentioned character, as well as by the presence of a pri-
mary tooth, which is wanting in that genus.

63

This new gcniis I formerly proposed when describing the above
mentioned Unio nndulafa, under the name of Monodonta ; but as
this term has been applied to a genus of Univalves, I have substi-
tuted that of Alasmidonta.

[A. N. S., vol. ii. p. 149, seqq., Jan., 1821.]

The terrestrial and fluviatile shells which form the subject of the
following pages, were chiefly obtained on the late expedition to the
Rocky Mountains, under the command of Major Stephen H. Long.
They are now deposited in the Philadelphia Museum, and consti-
tute, in the collection of that institution, a distinct arrangement.

A few descriptions are added to this essay, of shells discovered
in East Florida, Alabama, Pennsylvania, and New- York.

[J. A. N. S., vol. ii. p. 164, et seqq. Jan. 1821.]

Planorbis armigerus. — Shell dextral, brownish-horn color,
wrinkles obsolete ; spire perfectly regular, slightly concave ; suture
well impressed ; umbilicus profound, exhibiting the volutions ;
whorls four, longer than wide, obtusely carinated above, carina
obsolete near the aperture, a carina beneath continued to the aper-
ture ; aperture longitudinally subovate, oblique ; labrum blackish
on the edge ; throat armed with five teeth, placed two upon the
pillar side, of which one is large, prominent, perpendicular, lamelli-
form, oblique, and rounded abmptly at each extremity ; near the
anterior tip, is a small prominent conic acute one ; on the side of
the labrum is a prominent lamelliform tooth near the base, and
two slightly elevated, oblique, lamelliform ones above.

Length, \ of an inch nearly. Inhabits Upper Missouri.

Remarkable by the teeth ; but these are only discoverable by
the microscopical examination of the mouth, and they are situated
far within it.

P. TRivOLVis, BICARINATUS and PARVUS inhabit ponds of
water, in the vicinity of Council Bluff.

Planorbis parallelus. — Shell dextral, with very minute
transverse wrinkles, and regular, revolving, equidistant, parallel,
slightly elevated lines ; spire a little convex ; volutions four; aper-
ture longer than wide ; umbilicus exhibiting all the volutions.

Breadth, less than 3-20 of an inch. Inhabits Upper Missouri.

64-

This shell has evidently the habit of a Helix, and may probably
belong more properly to that genus, but having found it only in a
dried up pond, in company with a vast number of aquatic shells, I
refer it for the present to this genus.

Planorbis exacuous*. — Dextral, depressed, with an acute
edge.

Inhabits Lake Champlain. Cabinet of the Academy.

Shell depressed ; whorls four, striated across, wider than long,
not elevated above the suture, but a little flattened, sides obliquely
descending to an acute lateral edge, below the middle ; spire not
impressed ; suture not profoundly indented ; beneath, body whorl
flattened, on the inner edge rounded ; umbilicus regular, exhibit-
ing all the volutions to the apex ; aperture transversely sub-trian-
gular ; labrum angulated in the middle, arquated near its inferior
tip, the superior termination just including the acute edge of the
penultimate whorl.

Greatest breadth, rather less than 1 of an inch.

This species was found in Lake Champlain by Mr. Augustus
Jessup, who deposited it in the collection of the Academy. Only
two specimens occurred. It may be readily distinguished fi-om P.
parvus, by its more convex form above, the spire not being im-
pressed, and by its very acute lateral edge. It appears to be pretty
closely allied to Planorhis nitidus of Europe, but it is larger,
the umbilicus much more dilated, and the aperture does not em-
brace the penultimate whorl so profoundly.

Planorbis campanulatus. — Sinistral; whorls longer than
wide ; aperture sub-campanulate.

Inhabits Cayuga Lake. Cabinet of the Academy.

Shell sinistral, not depressed ; whorls four, slightly striate across,
longer than wide ; spire hardly concave, often plane ; body whirl
abruptly dilated near the aperture, and not longer behind the dila-
tation than the penultimate whirl ; suture indented, well defined
to the tip, the summits of the volutions being rounded ; aperture
dilated ; throat narrow abruptly ; umbilicus profound, the view
extending by a minute foramen to the apex.

[* It would certainly appear that Mr. Say intended this word to read
exacutus, as Dr. Gould suggests, — yet the same orthography is retained
in Long's Exp. — Ed.]

65

Greatest length of the body whirl, one-fourth of an inch Breadtyi
from tip of the hibruni, one half of an inch ; at right angles to the
last, two-fifths of an inch.

This shell abounds in some of the small streams, which discharge
into Cayuga lake, where it was collected by Mr. Jessup, who pre-
sented specimens to the Academy, and to me. It is readily dis-
tinguished from our other species, by the sudden dilatation of the
outer whirl, near the aperture in the adult shell, forming a large
oval chamber. The summit of the outer whirl, behind the dilated
portion, is not, or hardly elevated above the summits of the other
volutions.

Lymneus elongatus. — Shell horn color, tinged with reddish-
brown; spire elongated, tapering, acute; whirls six or seven,
slightly convex, wrinkled across ; body whirl, measured at the
back, more than half the total length ; suture moderately indented ;
aperture less than half the length of the shell ; labium with calca-
reous deposit.

Length, one inch and three-tenths.

Inhabits in considerable numbers, the ponds and tranquil watert<
of the Upper Missouri. It is very distinct from L. catascopiunij
by the much greater proportional length of the spire.

Lymneus columellus. — (Jour. Acad. Nat. Sciences, vol. i.
p. 14.) Var. a. Small, black — from Cold water creek of the Mis-
souri. This is most probably a distinct species ; we obtained but a
single specimen of it.

Lymneus reflexus. — Shell fragile, veiy much elongated, nar-
row, honey-yellow, tinctured with brownish, translucent, slightly
reflected from the middle ; volutions six, oblique, wrinkled trans-
versely ; spire more than one and an half times the length of the
aperture, acute, two or three terminal whirls vitreous ; body whirl
very little dilated ; aperture rather narrow ; labrum with a pah-
margin, and dusky red or blackish sub-margin.

Inhabits Lakes Erie and Superior. Total length, 13-10 — of the
aperture 11-20 of an inch.

This shell is remarkable for its narrow and elongated form, and
for the consequent, very oblique revolution of its whirls. When
viewed in profile, it has a slightly reflected appearance. It wat;
kindly sent to me for examination by my friends Messrs. S. B.

66

Collins, and D. H. Barnes, of New York, and was found in Lake
Superior by Mr. Schoolcraft. I recollect to have seen a specimen
two or three years since brought from Lake Erie, by James Grif-
fiths. It is proportionally longer than elongatus.

Lymneus appressus. — Shell elongated ventricose ; volutions
six ; spire regularly attenuated to an acute tip, rather shorter than
the aperture ; body whirl dilated, proportionally large ; aperture
ample ; columella with the sinus of the fold profound, callus per-
fectly appressed upon the shell, to the base.

Inhabits Lake Superior.

This shell exhibits very much the appearance of L. stagnalis,
but its body whirl is less proportionally dilated. The callus of the
labrum is perfectly appressed to the surface of the whirl even to
the base, exactly as in stagnalis. I have seen but a single wea-
thered and broken specimen, which was sent me for examination
])y my friends Messrs. Collins and Barnes, of New York. It was
found in Lake Superior, by Mr. Schoolcraft.

Since writing the above, Mr. Jessup presented me with sev-
eral specimens, which he collected in Canandaigua and Cayuga
lakes.

Lymneus elodes. — Shell oblong conic, gradually acuminated,
reticulate with transverse lines and longitudinal wrinkles ; whirls
rather more than six ; spire acutely terminated ; suture moderately
impressed ; aperture shorter than the spire ; labrimi, inner sub-
margin reddish obscure ; labium, calcareous deposit rather copious,
not appressed at base, but leaving a linear umbilical aperture ; body
whirl on the back longer than the spire.

Inhabits Canandaigua Lake.

Var. a. Whirls simply wrinkled across, the calcareous deposit
at base appressed to the surface of the whirl.

This species was found by Mr. A. Jessup ; it bears the most
striking resemblance to L. pahstris. The variety was found by
the same enterprising mineralogist at Morristown, New Jersey. I
have subsequently received specimens from Mr. S. B. Collins, of
New York, who procured them in a marsh near the Saratoga
Springs.

Lymneus destdiosus. — Shell oblong subconic ; whirls five,
very convex, the fourth and fifth very small, the second rather
large ; suture deeply indented ; aperture equal to or rather longer

67

than the spire ; labium, calcareous deposit copious, not perfectly
appressed at base, but leaving a very small umbilical aperture.
Inhabits Cayuga Lake. Length 7-10 of an inch.*
Found by Mr. Augustus Jcssup. It is closely allied to L. ehdes,
but the whirls are more convex, one less in number, and the two
terminal ones are proportionally smaller ; the callus of the labium,
also, near its inferior termination, is applied still more closely to
the surface of the body whirl.

Lymneus macrostomus. — Shell suboval; whirls five, body
whirl somewhat reticulated ; suture not profoundly indented ; spire
about two-thirds of the length of the aperture, acute ; aperture
much dilated ; labrum not thickened on the inner sub-margin.

Inhabits Cayuga Lake. Length one half of an inch, and up-
wards.

Imperfect specimens of this shell were found on the shore of
(Cayuga Lake, by Mr. A. Jessup, but they are sufficiently entire,
to exhibit considerable similarity to some varieties of L. auricn-
larius of Europe. It may readily be distinguished from L. catas-
copium, by its much more dilated aperture.

Lymneus emarginatus. — Shell rather thin, translucent ; volu-
tions four, very convex; body whirl large; suture deeply im-
pressed ; spire somewhat eroded ; mouth two-thirds of the length
of the shell.

Length nearly 4-5 of an inch ; of the mouth, half inch.

Inhabits Lakes of Maine. This species was discovered by Mr-
Aaron Stone.

It is a rather larger and considerably wider shell than L. catas-
copiuni, and the emargination visible on a profile view of the
umbilical groove is far more profound.

Physa GYRiNA. — Shell heterostrophe, oblong; whirls five or
six, gradually acuminating to an acute apex; suture slightly im-
pressed ; aperture more than one half, but less than two-thirds of
the length of the shell ; labrum a little thickened on the inner
margin.

Length rather less than one inch.

Inhabits waters of the Missouri.

[* The text gives 7-20ths, which is corrected by Mr. Say in the remarks
on L. humilis. — Ed.]

68

Of this species, I found two specimens at Bowyer creek, near
Council Bluff. It differs from P. heterostropha in magnitude, in
having a more elongated spire, and less deeply impressed suture.

Physa elongata. — Shell heterostrophe, pale yellowish, very
fragile, diaphanous, oblong; whirls six or seven; spire tapering,
acute at the tip ; suture slightly impressed ; aperture not dilated,
attenuated above, about half as long as the shell ; columella much
narrowed near the base, so that the view, may be partially extended
from the base towards the apex.

Inhabits shores of Illinois. Length, 7-10 inch. Greatest breadth,
8-10 nearly.

Animal deep black, immaculate, above and beneath ; tentaeula
setaceous, a white annulation at base.

In the fragility of the shell, this species approaches nearest to
columella. It is very common in stagnant ponds on the banks of
the Mississippi. When the chell includes the animal, it appears
of a deep black color, with an obsolete testaceous spot near the base
on the anterior side. Its proportions ai-e somewhat similar to those
of P. liypaorutn.

Physa heterostropha (Nicholson's Encyc.) — Is veiy com-
mon in ponds of the Missouri as far as Council Bluff.

Valvata tricarinata (Nicholson's Encyc.) occurs in consid-
erable numbers in ponds, in the vicinity of Council Bluff.

Paludina ponderosa. — Shell somewhat ventricose, much
thickened, olivaceous or blackish ; spire not much elongated, much
shorter than the aperture, eroded at tip, but not truncated ; whirls
five, slightly wrinkled across ; suture profoundly impressed ; aper-
ture subovatc, more than half the length of the shell ; labium with
much calcareous deposit, and thickened into a callosity at the supe-
rior angle ; within tinged with blue.

Inhabits Ohio River.

Greatest length, one inch and 11-20. Transverse diameter one
inch and 1-10.

This shell is common ' at the falls of the Ohio, and is a very
remarkably thick and ponderous species. It bears a striking re-
semblance to P. decisa, and has, without doubt, been generally
considered as the same ; but it differs from that species in being
much more iucrassated and heavy ; and although much decorti-
cated and eroded upon the spire, the tip is not truncated. In the

69

labrum also is a distinctive character; by comparison this part will
be perceived to be less arquatcd in its superior limb, than the cor-
responding part in dccisa.

Paludina INTEGRA. — Shell olivaccous, pale, conic ; whirls six,
wrinkled across ; spire rather elongated, entire at the apex ; suture
profoundly indented; aperture subovate, less than half of the
length of the shell.

Inhabits the waters of the Missouri. Length i inch.

Very much resembles P. decisa, the spire, however, is more
elongated, and never truncated at the apex, but always acute.

Paludina porata. — Shell obtusely-conic or subglobose ; volu-
tions four, convex, obsoletely wrinkled across ; spire obtuse ; labrum
and labium equally rounded, meeting above in a subacute angle ;
the upper edge of the latter appressed to the preceding whirl ;
umbilicus very distinct.

Inhabits Cayuga Lake. Cabinet of the Academy.

This species, which was found by Mr. Jessup, is rather larger
and more globose than P. limosa to which it is allied, and has a
more distinct umbilicus. It resembles P. decvpiens of Ferrussac,
but is much less acute, and rather smaller.

Paludina lustrica. — Shell conic; whirls slightly wrinkled,
convex ; suture profoundly indented ; aperture oval, nearly orbi-
cular ; labrum with the superior edge not appressed to the pre-
ceding whirl, but simply touching it; umbilicus rather large,
rounded.

Length, less than 1-10 of an inch. Cabinet of the Academy.

The smallest species I have seen. The aperture somewhat re-
sembles that of a Valvata, to which genus it may probably be
referrible. Mr. Jessup obtained two specimens on the shore of
Cayuga Lake.

Melania canaliculata. — Shell tapering, horn-color; volu-
tions about seven, slightly wrinkled ; spire towards the apex much
eroded, whitish ; body with a large obtuse groove, which is obso-
lete upon the whirls of the spire, in consequence of the revolution
of the suture on its inferior margin ; this arrangement permits the
superior margin of the groove, only, to be seen on the spire, in the
form of an obtuse carina on each of the volutions ; aperture bluish-
white within, with one or two obsolete revolving sanguineous lines ;

70

labrum sliglitly undulated by the groove, and with a distinct sinti?
at the base of the columella.

Inhabits Ohio River.

Length, one inch and one tenth. Breadth, 3-5 of an inch.
Grreatest transverse diameter more than 2-5.

Very common at the Falls of the Ohio River. It is probably
the largest species of this genus in the United States, and may be
readily distinguished from its congeners by its broad groove.

Melania elevata. — Shell gradually attenuating to the apex,
slightly and irregularly wrinkled, olivaceous ; suture not deeply
impressed ; volutions nine or ten, with several more or less elevated
revolving lines, of which one being more conspicuous gives the
shell a carinated appearance ; aperture oblique, equalling the length
of the second, third, and fourth volutions conjunctly.

Length, one inch. Breadth two-fifths. Inhabits Ohio River.

Distinct from our other species, by the elevated revolving lines.

Melania Conica. — Shell conic, rapidly attenuating to an acute
apex, very slightly wrinkled, olivaceous ; suture not deeply im-
pressed ; volutions seven or eight ; aperture oblique, equalling the
length of the second, third, and fourth whirls conjunctly.

Var. a. With from one to three, revolving, rufus or blackish
lines.

Length, nearly 3-5 inch. Of the aperture, I inch. Inhabits
Ohio River.

May be readily distinguished from M. virginica by the much
more rapid attenuation of the spire, and in the proportional differ-
ence in the length of the aperture, which in the virginica is not
more than equal to the length of the second and third whirls.

MelAnia pr^rosa. — Shell subglobular, oval, horn color; volu-
tions three or fOur, wrinkled across ; spire very short, much eroded
in the old shell, so much so as to be sometimes not prominent
above the body whirl ; body whirl large, ventricose, with a very
obtuse, slightly impressed revolving band; aperture suboval, abov€
acute and eifuse ; withip on the side of the exterior lip about four
revolving purplish lines, sometimes dotted, sometimes obsolete or
wanting ; labium thickened, particularly at the superior tcmiina-
tion near the angle, and tinged with purplish ; ba,se of the colum-
ella somewhat elongated and incurved, meeting the exterior IJp at
an angle.

71

Length, about 4-5 inch. InliabitvS Ohio River.

Found in plenty at the falls of the Ohio. The spire is remarkably
carious in the older shells, and the penultimate whirl, between the
aperture and the spire, is also remarkably eroded in many older
shells. The spire in the young shell is entire, and but little promi-
nent, though acute, and the bands are distinct on the exterior of
the shell. This shell does not seem to correspond with the genus
to which I have, for the present, referred it; and owing to the
configuration of the base of the columella, if it is not a Melanopsis,
it is probable its station will be between the genera Melania and
Acathina. I propose for it the generic name of Anculosa.

Melania armiqera. — Shell tapering, brownish-horn color;
volutions about six, slightly wrinkled ; spire near the apex eroded,
whitish ; body whirl with a revolving series of about five or six dis-
tant, prominent tubercles, which become obsolete on the spire, and
are concealed by the revolution of the succeeding whirls, in conse-
quence of which arrangement there is the appearance of a second,
smaller, and more obtuse subsutural series of tubercles on the body
whirl ; two or three obsolete, revolving, reddish-brown lines ; aper_
ture bluish-white within ; a distinct sinus at the base of the colu-
mella.

Inhabits Ohio River. Length about one inch.

Distinguished from other N. American species, by the armature
of tubercles.

Bulla fluviatilis. — Shell suboval, pellucid, pale yellowish
white, finely wrinkled ; volutions three ; body whirl large, with a.
prominently capinated shoulder bounding the spire ; spire perfectly
flat or slightly concave, giving to the shell a perfectly truncated
appearance in that part ; aperture longer than the columella, ob-
long-ovate, extending beyond the tip of the spire ; umbilicus pro-
found, edged by a slight carina.

Length of the aperture one-fifth of an inch. Greatest breadth
somewhat less. Inhabits the River Delaware.

This species seems to be rather rare ; ij; was discovered by Mr.
Aaron Stone, deeply imbedded in the mud ; Mr. William Hyde, of
this city, has since found specimens of it amongst some dead shells
of other genera assembled in a small inlet of the river.

72

[J. A. N. S. Vol. ii. p. 281, et seqq. June, 1822.]

During oecagional visits to our sea coast, and particularly on a
journey to East Florida, in company with Messrs. Maclure, Ord,
and T. Peale, I availed myself of every favorable opportunity to
collect marine shells, whilst engaged in the pursuit of other and
more favorite objects.

No naturalist, however conversant he may be with marine pro-
ductions, can examine our sea coast for a single day with ordinary
assiduity, without discovering something new or interesting to re-
ward his labors, and to gratify his laudable curiosity. Accordingly
these researches furnished my cabinet with a great number of
shells which were unknown to me, and of which many appeared to
be unnoticed in those works on conchology to which I could obtain
access.

But supposing that these apparently new species, many of which,
being either abundant in individuals, or attractive to the eye by
beauty of coloring or symmetry of fonn, had been often observed
by foreign naturalists and collectors, and in all probability had long
since been transmitted to Europe, and perhaps published in some
splendid volume, or, to us, obscure tract, of which the title had not
yet reached this country, I was induced to relinquish any further
investigation of the subject, and to dwell upon the hope of receiv-
ing more exotic information than we already possessed.

This course I was more readily inclined to pursue, in conse-
quence of being informed that an American zoologist had already
commenced the examination of our marine shells, with the inten-
tion of publishing the result of his observations. Several years
have, however, since elapsed Avithout any addition to our know-
ledge in this department of Natural History, from the pen of an
American author.

Several naturalists who now devote a portion of their attention
to conchology, and particularly to that of the United States, having
recently requested me to publish an account of our marine shells,
I have thought it might be useful to communicate to them imme-
diately descriptions of those which I do not find to be distinctly
described by attainable authors. Such species or varieties, only,
are made known in the following essay.

With a view to condense this paper as much as possible, I have
omitted the generic characters, but at the same time, I have been

73

careful to subjoin to the generic names that are liere adopted, ab-
breviations of the author's names, who formed them respectively,
or whose generic definitions I have followed.

Type and Class MOLLUSCA GASTEROPODA.

Patella amcena. — Shell oblong-oval, whitish reticulated with
reddish-brown, and sculptured with numerous minute concentric
wrinkles and close set radii ; margin entire j apex placed behind the
middle, and pointing backwards.

Coast of New England States.

Length of a small specimen, seven-twentieths, breadth one-fifth
of an inch. Breadth of a larger one three-tenths, nearly. My cabinet.
^It may be readily distinguished in general by the beautiful
reticulated disposition of the rufous color, inclosing small irregularly
oval, white, or yellowish-white spots. They sometimes, however,
are of a uniform greenish or brownish color. Several specimens
of this species were communicated to me by Mr. Aaron Stone, who
found them on the coast of Maine.

FissuRELLA alternata. — Shell oblong-ovate, moderately
thick, cinereous or dusky, with equal concentrated lines, crossed
by alternately larger and smaller radii, all which are equable or not
dilated in any part ; vertex placed nearer the smaller end ; perfora-
tion oblique, oblong and a little contracted in the middle ; within
white ; margin simply crenate ; apex with an indented transverse
line at the larger end of the perforation.

Length four-fifths of an inch. Breadth three-fifths. Height
more than two-fifths. Inhabits the coast of the United States.
Cabinet of the Academy, and Philadelphia Museum.

Bears a general resemblance in its sculpture to F. grse,ca, but the
radii are not dilated at the points where they are crossed by the
concentric lines. I have specimens from the coast of Maryland
that measure one inch and a half in length.

Crepidula fornicata ? var. — Shell transversely wrinkled,
varying in convexity, with obsolete longitudinal, undulated, rufous
lines ; one side more oblique than the other ; apex excurved, a little
prominent, but not separated from the body of the shell, and gene-
rally united with the margin of the aperture ; aperture suboval ;
diaphragm a little concave, occupying at least half of the length,
edge generally declivate.

74

Inhabits the coast of the United States. Lengtli two inches .
Cabinet of the Academy, and Philadelphia Museum.

Seems to diifer from the species as described by Roissy in Sonni.
Buff, by having lateral lineations instead of spots. It may very
probably be a distinct species.

Crepidula depressa. — Shell very much depressed, trans-
versely v?rinkled, nearly equilateral ; epidermis pale yellowish-
brown ; apex not curved, forming a simple acute terminal angle
upon the margin of the aperture ; aperture subovate ; within white .;
diaphragm convex, edge contracted in the middle and at one side

Length four-fifths of an inch. Inhabits the coast of the United
States.

Cabinet of the Academy, and Philadelphia Museum. Differs
from the preceding in the form of the beak, which is never
arquated.

Crepidula glauca. — Shell thin, convex, glaueus, with minute
transverse wrinkles ; apex conic, acute, not excurved, but declining
and distinct from the margin of the aperture ; aperture oval-orbi-
cular ; within entirely reddish-brown ; diaphragm plain or convex,
less than half the length of the shell, edge widely contracted in
the middle.

Length about half an inch. Inhabits the coast of the United
States.

Cabinet of the Academy and Philadelphia Museum. Very dis-
tinct from the preceding species.

Crepidula plana. — Shell depressed, flat, oblong oval, trans-
versely wrinkled, lateral margins abruptly deflected ; apex not
prominent, and constituting a mere terminal angle, obsolete in the
old shells ; within white ; diaphragm occupying half the length of
the shell, convex, contracted in the middle and at one side.

Length one and one-tenth' of an inch. Inhabits the coast of the
United States. Cabinet of the Academy and Philadelphia Museum.

A remarkably distinct species, the surface of the shell is flat,
and sometimes slightly concave. The young shell is generally or-
bicular, and gradually becomes proportionally more elongated as it
increases in size. I have found it on the coasts of Maryland,
Carolina, Georgia and East Florida, and my brother, Mr. Benjamin
Say, discovered it on the shores of New Jersey.

Crepidula intorta ? var. — Shell convex, ovate, with about

75

twenty elevated, somewliat undulated, lines, with alternate smaller
ones ; lines somewhat confused on the convex side of the shell, the
larger lines with a few slightly elevated, very thick fornicated
tubercles; apex curving laterally, tip pointing upwards and not
elevated from the body of the shell.

Inhabits the southern coast.

Of this shell I found but a single specimen, which is very im-
perfect. It seems to correspond very well with the description of
G. inlorta of the coast of England, with the exception of the form
of the vertex, which in that species is said to turn downwards,
whereas, in our shell, it not only turns downwards, but the curve
is continued until the tip points upwards.

Crepidula convexa. — Shell very convex, obsoletely wrinkled
or glabrous, One side vertical, the other oblique ; apex prominent,
decurved, slightly inclining towards the oblique margin, tip gene-
rally free and extending lower than the edge of the aperture ;
aperture suboval ; diaphragm less than half the length of the
shell, edge simply arquated.

Length three-fifths of an inch. Inhabits the coast of the United
States. Cabinet of the Academy and Philadelphia Museum.

This species is not uncommon, particularly upon our southern
coast. The description is drawn from what are termed dead shells,
but 1 have one specimen which is varied with rufous and whitish.

Oliva mutica. — Shell suboval, white, or yellowish-white ; body
whirl with about three revolving maculated bands of pale rufous,
of which the superior one is continued upon the spire, the inter-
mediate one is dilated so as to be sometimes confluent with the in-
ferior one, which is narrowest j spire short ; suture very narrow ;
colimiella destitute of striae.

Length more than two-fifths of an inch. Inhabits the southern
shores. Cabinet of the Academy and Philadelphia Museum.

A common shell, varying somewhat in color ; the bands are
sometimes deep reddish-brown, sometimes livid, rarely all united,
and offering only a white line near the base. It seems allied to
the 0. zonalis as described by Lamarck, but is a larger species.

BucciNUM ORNATUM. — Shell subturbinated, with about two
bands of arched scales. .

Inhabits the coast of East Florida. Cabinet of Mr. William
Hyde.

76

Shell subturbinated, with numerous revolving striae and interme-
diate grooves ; wliitisli cinereous, witli rufous bands, and transverse,
irregular wrinkles, and obsolete undulations separated by somewhat
rugged incisures ; near the base is a band of ten or twelve elevated
arched scales, disappearing in the aperture ; whirls flattened above
the shoulder, and armed in that part with \uidulated lamellw,
whicli on the shoulder are elevated into prominent concave spines ;
spire prominent; whirls transversely undulated, the arched scales
disappearing towards the tip ; aperture eflFuse ; throat varied with
pale green and yellowish, the rufous bands being very distinct ;
umbilicus none.

Length four inches. Aperture two and three-fourths inches.
Spire one and a half inch.

This fine coronated shell, seems to agree better with the descrip-
tions of B. armigernm and hezoar, than with those of any other
species, as far as I have been able to ascertain. To the latter it
seems to be more closely related, with Agcnville's figure of which
it corresponds in the form and position of the basal band of scales,
excepting that it has this band far more oblique ; that figure, how-
ever, is much less elongated than our shell, and it appears to have
a double series of prominent scales on the shoulder. The hezoar,
moreover, is described to be umbilicated, a character which does
not exist in our species.

COLOMBELLA AVAR A. — Shell Small, covered with a dirty
brownish pigment, beneath which it is whitish reticulated or macu-
lated with rufous ; spire elevated, acute ; volutions eight, with
spiral impressed lines, and transverse elevated obtuse costa ; the
costA upon the body whirl are terminated at the middle, and are
about eleven in number ; labium with a distinct plate crenated on
the submargin j labrum denticulated within, but not very percepti-
bly thickened on the inner middle.

Length less than half an inch. Lihabits the coast of the
Southern States. Cabinet of the Academy and Philadelphia Mu-
seum.

Does not fully correspond with the characters of this genus, as
the labrum is not very distinctly dilated on the inner middle, and
the spire has the elevation of a Mitra.

It is a common species, and occurs as far north as the coast of
Mainland.

77

Nassa vibex. — Shell canccllate, ventricose, cinereous or pale
reddish-brown, with two or three irregular, sometimes obsolete
darker fascia ; body whirl with twelve thick, prominent costa, and
about as many revolving filiform lines, which are not much ele-
vated, and but simply crenate the costa and lip ; labrum incrassated,
with about two more prominent teeth within ; labium callous ; spire
short, rapidly attenuated to an acute tip.

Length three-fifths of an inch. Inhabits the southern and mid-
dle coast. Cabinet of the Academy and Philadelphia Museum.

Rather rare. I found but four specimens. For the locality of
the coast of the Middle States, I am indebted to my brother, Mr.
B. Say, who brought me a specimen from the shores of New Jersey.

Nassa trivittata. — Shell conic acute, yellowish-white, can-
cellate so as to appear granulated, granules prominent, equidistant j
ten revolving impressed lines on the body whirl, and a somewhat
more conspicuous groove near the summit of each volution ; spire
as long or longer than the body, and with a rufous revolving line
near the suture ; body whirl trilineate with rufous, the lines placed
one near the suture, one on the middle, and the third rather
darker, at the origin of the beak ; suture regular and deeply im-
pressed ; beak distinguished by a profound depression, from the
body whirl, slightly reflected ; labrum not incrassated, with raised
lines within upon the fauces which do not extend quite to the
edge of the lip ; labium distinctly lamellar, with an obsolete fold
of the basal edge, and a tooth near the superior junction with the
labrum.

Length about seven-tenths of an inch. Inhabits the Middle and
Southern States. Cabinet of the Academy and Philadelphia Mu-
seum. A very common species.

It somewhat resembles Maton and Rackett's figure of Bmcinum
macula, (Linn. Trans. Loud. vol. 8,) in the cancellated appearance,
but it is a longer shell and destitute of the incrassated aperture.
This species is closely allied to the genus Phos of Montfort, by the
striated labrum, and the projection or slight fold at the base of the
columella, which, in the system of that author, is an essential one.

Nassa obsoleta. — Shell ovate-conic, subacute, cancellate, ex-
hibiting a granulated appearance, dark reddish-brown, or blackish,
sometimes tinged with olivaceous ; spire shorter than the body j
suture not deeply impressed ; beak not distinguished from the body

78

whirl by any profound depression, and not prominent; labrum
within lineated with elevated, abbreviated or interrupted lines, not
incrassated, purple-black ; columella at base with a prominence or
fold.

Length three-fifths of an inch. Inhabits the coast of the United
States. Cabinet of the Academy and Philadelphia Museum.

Animal. — Foot as long as] the shell, rounded before, with the
anterior angles elongated, conic, reflected and resembling short
tentacula ; head not extended beyond the shell ; eyes above the
base of the tentacula, placed on the exterior side and black ; tenta-
cula setaceous, abruptly smaller above the eyes ; trunk cylindrical,
the suture beneath exserted over the head, half as long as the
shell and veiy conspicuous.

Inhabits the shores of our estuaries in great numbers. When
left by the recess of the tide, they collect together in small pools,
or crawl in pursuit of the retiring water ; but when left quite dry,
they biuTow in the sand so as to conceal themselves from the action
of the sun, and patiently await the returning tide. They assemble
about dead crabs and other animals, and aj^pear to feed upon them.

This shell is more frequented by Pagurus longicarjms than any
other ', it bears a general resemblance to the preceding species, but
is sufficiently distinguished by being less elongated, the suture and
impressed lines not being so profound and the beak less prominent
and distinct ; the color is also very different.

It resembles the shell represented by Lister, plate 276, fig. 32.
" Buccinum B. r. parvum nigrum ex toto laeve." It is usually
covered by a blackish pigment which obscures its character :
within the aperture, on many specimens, a dull or obsolete whitish
line may be seen.

The description shows the near approach of this shell to Mont-
fort's genus jP/<o.s, to which it is as closely allied as the preceding
species.

Nassa acuta. — Shell conic acute, whitish, cancellated so as to
appear gi-anulated, granules prominent, somewhat transverse, ine-
quidistant, the transverse grooves being more profound and dilated
than the spiral ones, which are six in number ; spire longer than
the body whirl, slender towards the tip, acute ; suture impressed,
but not profoundly ; beak distinguished by a depression from the

79

body whirl, and slightly reflected ; labriim incrassated, and with
olevated lines upon the fauces, which do not attain the edge of the
lip.

Length half an inch. Inhabits the shores of the Southern
States. Cabinet of the Academy and Philadelphia Museum.

A species which not unfrequently occurs, it is very distinct from
the two preceding ones, and may be readily distinguished from them
by the incrassated outer lip.

Cerithium dislocatum. — Shell attenuated, acute at the apex ;
volutions with numerous, minute, revolving, impressed lines, and
from fifteen to eighteen transverse, elevated costa to each volution,
which are dislocated near the summit of each volution by a revolv-
ing line, as deeply impressed as the suture.

Length one and one-fourth of an inch. Inhabits the coast of
the United States. Cabinet of the Academy and Philadelphia
Museum.

This shell is very common on the Southern shores, particularly
on that of East Florida, but I have also found specimens on the
shore of Mai-yland. Lister, tab. 979, fig. 36, represents a shell very
similar to this, but larger.

The effect of the impressed line, which revolves above the mid-
dle of the volutions, is, to separate the longitudinal raised lines
into two series, whereof the lines of the superior series are much
shorter and thicker than the others.

Fusus CINEREUS. Shell with a cinereous epidermis, reddish-
brown beneath ; volutions cancellate, the transverse costa eleven,
robust; revolving lines filiform, irregularly alternately smaller,
crenating the edge of the exterior lip, which is acute, and alterna-
ting with the raised lines of the fauces ; fauces tinged with choco-
late color ; beak short, obtuse, not rectilinear ; labrum not incras-
sated.

Length one and one-fourth of an inch. Inhabits the estuaries of
the United States. Cabinet of the Academy and Philadelphia
Museum.

I have frequently found this species in oozy places of the bay
of G-reat Egg Harbor, and on the Eastern shore of Maryland. My
brother, B. Say, ascertained that it is also an inhabitant of the coast
of New Jersey.

80

Ranella caudata. — Shell pale reddish-brown, cancellate, with
eleven robust costa to the body whirl, and several revolving filiform
lines passing over them, which are more prominent upon the varice
of the aperture, terminate at its inner edge, and there alternate
with the raised lines of the fauces ; volutions flattened at their
summits, abruptly declining to the suture ; canal coarctate, rather
longer than the spire ; beak rectilinear, reflected at the tip.

Length one inch. Inhabits the coast of the United States.
Cabinet of the Academy and Philadelphia Museum. A rather
common species.

This generic name I think objectionable, inasmuch as it borders
too closely upon Renilla, which designates a genus of the class
Polypi of Lamarck. Montfort's appellation Buffo is not preferable
for a similar reason, as it would be liable to be confounded with
Buffo, a genus of Reptilia.

FuLGUR PYRULOIDES. — Shell with spiral strise alternately larger;
whirls white, transversely lineated with ferruginous lines, inter-
rupted or obsolete on the middle ; above flattened, unarmed ; spirt
short ; suture profoundly canaliculate.

Seha, Vol S,pl QS,ffg. 19, 20 ?

Lister, Conch.pl. 877 ?

Length three inches and four-fifths. Breadth one inch and
one-tenth. Inhabits the Southern coast. Cabinet of the Academy
and Philadelphia Museum.

At first sight this species would be referred to the genus PyrtUa,
but upon inspection it will be observed to have a fold on the colu-
mella. I formerly mistook the young shells for those of F. canicu-
lata or gramim, which they much resemble in form, in the grooved
sutures, and in the spiral striae ; but they difi"er from them in
having a much less elevated spire, by being entirely destitute of
armature, either of spines or tubercles, upon the angulated ridge
of the volutions, and by being marked with colored lines. In this
last character they approach F. perversus, but they will not be mis-
taken for that species.

As the shell advances in growth, the acute edge of the depressed
top of the whirls becomes obtuse, and in the adult shell it is
nearly obsolete ; in which state the almost regular curve of the
whirl is very like that of Pyrula.

Seba's figures above quoted, are probably intended for this

81

species ; they certainly rcpreseut it very well as it appears in the
young state.

I think it highly probahle that this is the Bulla Ficus, Var. b.
Gmel., which Dillwyu describes under the name of Bulla jyyrvm,
with the country of which he was unacquainted.

Pyrula papyratia. — Shell inflated, thin, white, with small,
• pale, rufous spots, within pale, dull purplish-red ; whirls with nu-
merous spiral strias, which are alternately larger, crossed by smaller
striae.

Length four inches and one-tenth. Greatest breadth two inches
and one-fifth nearly. Inhabits the coast of Georgia and East
Florida. Cabinet of the Academy.

This species has been hitherto confounded with P. ficus, U)
which indeed it is closely allied, but differs in having the beak
proportionably longer, and in being but slightly spotted.

It is also an inhabitant of the West Indies.

Turbo irroratus. — Shell thick, greenish or pale cinereous,
with numerous revolving, elevated, obtuse, equal lines, which are
spotted with abbreviated brownish lines ; suture not indented 5
spire acute ; labium incrassated, yellowish-brown ; labriim within
white and thick, at the edge thin, and lineated with dark brown-
ish ; throat white ; columella with an indentation ; operculum
coriaceous.

Length four-fifths of an inch. Inhabits the coast of the United
States. Cabinet of the Academy and Philadelphia Museum.

This has the general appearance of T. littoreus, but is sufficiently
distinct by the above characters ; the calcareous deposit on the
labium is copious.

An inhabitant of our estuaries of the Middle and Southern
States. I have found them on the Eastern shore of IMaryland,
and on the coast of Carolina, Georgia and Florida ; and my brother
obtained a specimen on the coast of New Jersey, of the length of
one inch and one-tenth nearly. Mr. Cuvier would place this shell
in the genus Paludina.

Turbo canaliculatus. — Shell thin, globular, with about four
volutions ; body whirl with four profound striated grooves, and
and several smaller ones near the base and suture ; suture profound-
ly indented ; color pale reddish-brown, immaculate.

82

Length about one-tenth of an inch. Inhabits the Southern
coast.

Animal. — Foot shorter than the shell, oval; tentacula rather
robust, filiform, half as long as the foot ; eyes at the external base
of the tentacula.

I have obtained but a single individual of this species. If it is
only an immature specimen, we know nothing of the parent of
it.

Turbo palliatus. — Shell suboval, not remarkably thickened ;
whirls four or five, wrinkled transversely ; spire short, convex,
obtuse, much shorter than the aperture; suture moderately in-
dented.

Length about one-third of an inch. Greatest breadth about the
same. Inhabits the shores of the New England States. Cabinets
of Mr. Aaron Stone, Mr. Wm. Hyde and my own.

This species was found by Mr. Aaron Stone on sea-weed, about
low water mark. It is often variegated with olivaceous and white,
or green and yellowish, so as to exhibit a reticulated appearance ;
but they are veiy frequently covered with a greenish, or red-
dish-brown pigment, and sometimes with a plain yellowish-white
immaculated one. The shell within is very often of a dark red-
dish-brown color, with the oral margin whitish ; but the same part
is sometimes entirely whitish.

Turbo obligatus. — Shell suboval, not thickened ; whirls five,
transversely wrinkled, and longitudinally striated with obtuse
slightly elevated lines ; spire short, much shorter than the aperture ;
suture indented.

Length about one-third of an inch. Greatest breadth about the
same. Inhabits Portland, Maine. Cabinets of Messrs. Stone,
Hyde and Say.

This species strongly resembles the preceding, but is distin-
guished by the elevated, obtuse, revolving lines, or acute impressed
ones. The colors are greenish, olivaceous, or whitish, with darker,
irregular, transverse lines or shades, and the throat is dark reddish-
brown, the margin of the mouth whitish. It is vciy possible that
it is only a variety of the preceding.

Turbo vestita. — Shell conic, rather thin ; whirls about six,
rounded, transversely wrinkled ; spire as long as the aperture ;
suture deeply impressed.

83

Length two-fifths of an inch. Width more than three-tenths.
Inhabits Maine. Cabinets of Messrs. Stone, Hyde and Say.

We are indebted for this shell to Mr. Aaron Stone. It is com-
monly invested with a dirty greenish-white pigment, beneath which
it is sometimes reticulated with abbreviated yellowish lines, on a
brown or dusky ground.

SCALARIA LINEATA. — Shell brownish, elongated, with about
seven volutions ; costa robust, obtuse, little elevated, and from
seventeen to nineteen on the body whirl; body whirl with gener-
ally a blackish, more or less dilated line, which is nearly concealed
on the volutions of the spire by the suture ; margin of the mouth
robust, white, more dilated at the columella base.

Length about half an inch. Inhabits the southern coast. Cabinet
of the Academy and the Philadelphia Museum.

Very much resembles Turho clathratulus of Montague, which is
figured by Maton and Rackett as a variety of T. clathrus, (Trans.
Lin. Soc. Lond. vol. 8, pi. 5, fig. 1,) but the lip is more robust,
and the basal portion of that part is more dilated than the quoted
figure of that species. It is possible, however, that it is only a
variety of that species.

TuRRiTELLA ALTERNATA. — Shell dusky; acute at the apex;
volutions eight, with about eight unequal, revolving, slightly ele-
vated lines, which are maculated with rufous, and decussated by
transverse, elevated, obtuse lines, which are obsolete below the
middle of the body whorl and prominent on the spine ; labrum not
thickened, a slight indentation at its base.

Length one-fifth of an inch. Inhabits the coast of the United
States. Cabinet of the Academy and Philadelphia Museum.

Animal. — Foot longer than the aperture of the shell, rather
acute behind, and truncated a little convexly before ; tentacula
filiform, cylindrical, obtuse at tip, nearly as long as the foot, white,
annulate with brownish lines ; eye at the external base of the ten-
tacula, not prominent ; rostrum about one-third the length of the
tentacula ; operculum blackish.

The shell, when taken from the water, becomes whitish-cinereous.
They abound amongst Fiiciis, and sometimes on the shell of
Limidus Polyphemus. The animal considerably resembles that of
Melania Virginica as respects form, and in common with many

84

fresh water shells it possesses the power of gliding along the siu-
face of the water, with the shell downward.

This shell is something like T. reticulata, but the sculpture is
less profound, and it has never any appearance of varices, or in-
crassation of the labrum.

TuRRiTELLA IMPRESSA. — Shell dusky, acute at the apex ; volu-
tions six, with about four acute, impressed, revolving lines ; labrum
not thickened, a slight indentation at its base, and a projecting
angle within its middle.

Inhabits the coast of Maryland. Length more than one-eighth
of an inch.

I have seen but two specimens of this species. The aperture
is precisely similar to that of the preceding species.

TuRRiTELLA BISUTURALIS. — Shell thin, pellucid, small, conic ;
whirls five, wrinkles almost obsolete, a revolving impressed line
near the suture ; suture not deeply impressed ; spire gradually
tapering, rather longer than the aperture; aperture rounded at
base, and perfectly entire.

Length rather more than one-tenth of an inch. Inhabits Boston
harbor. My cabinet.

I am indebted to Mr. Aaron Stone for this small species of
Turritella. It is distinguished from all others that I have seen,
by the single impressed line, which revolves near the suture.

Bulla solitaria. — Shell remarkably thin and fragile, pellu-
cid, oval, narrowed at base, with numerous impressed revolving
lines, and transverse very obtuse wrinkles ; aperture surpassing the
tip of the shell ; spire none, substituted by an umbilicus ; umbilicus
of the base none.

Less than half an inch. Inhabits the southern coast of the
United States.

I found a specimen of this species of Bulla on the coast of
Maryland, but have not seen another. It is probable that it is
rare. It approximates to the description of B. hydatu, but it can
hardly be the same, as it is more oblong than the species B.
naucum agreeably to the figure in the Encyc. Meth., which spe-
cies is referred to by Dillwyn, as being of the same form with
hydatis.

Melampus bidentatus. — Shell thin, fragile, dirty-brownish ;

85

very little elevated, obtuse ; body whirl with minute transverse
wrinkles, and revolving impressed strias ; labium bidcntate, the
superior tooth transverse, prominent, terminating at the exterior
edge of the columella ; labrum with four or five elevated stria?, not
attaining the edge ; base not contracted.

Length nine-twentieths of an inch.

Animal about as long as the shell, and the foot is transversely
bifid ; tentacula somewhat wrinkled, cylindrical, rather smaller to-
wards the tips, which are obtuse or rounded; eyes placed at the
inner base of the tentacula ; rostrum somewhat wrinkled, nearly as
long as the tentacula, bi-lobate before; foot, anterior segment
emarginate behind, posterior segment bifid at the extemity; all
above, with the exception of the tenacula and rostrum, glabrous,
reddish-brown, beneath paler.

Inhabits East Florida. Cabinet of the Academy and Philadel-
phia Museum.

Var. a. With three or four fuscous revolving lines ; base of the
aperture narrower than in the species.

Length seven-twentieths of an inch. Inhabits the coast of
Maryland and New Jersey.

These shells inhabit the salt marshes, and have the habit of
crawling up the culms of grasses, and other plants. I observed
theiu to be veiy nvimerous near the mouth of St. John's river.
It is sufficiently distinct from the M. conifortnis by the paucity of
striae on the labrum.

The variety is a very common inhabitant of our coast, and is
very possibly a distinct species, as it is lineated and is narrower at
base ; if so, it may be called lineatus.

Grreat numbers of this species are devoured by the dusky duck
(Anas obscura,) and perhaps by other birds.

Natica DUPLICATA. — Shell thick, sub -globose, cinereous, with
a black line revolving on the spire above the suture, and becoming
gradually diluted, dilated, and obsolete in its course ; within brown-
ish-livid ; a large incrassated callus of the same color extends
beyond the colimiella, and nearly covers the umbilicus from above ;
umbilicus with a profound sulcus or duplication.

G-reatest length about two inches. Greatest breadth rather
more. Inhabits the coast of the United States. Cabinet of the
Academy and Philadelphia Museum.

, 86

Very numerous upon almost the whole extent of our coast. The
spire in some specimens is much more elevatrd than in others, and
the duplication within the umbilicus, is sometimes partially con-
cealed by the projecting callus.

In the collection of the Accademy of Natural Science is a
species from Candia, presented by Mr. S. Hazzard, which very
much resembles this, but it differs in being destitute of the black
line, and in having the umbilicus partially covered from the side,
leaving only a linear, semicircular, lateral opening. Another speci-
men from India strongly resembles it, and is also marked with the
black line, but there is only a circumscribed callus extending
laterally, leaving a large umbilicus, and marked transversely by a
groove.

I formerly referred this species to N. rugosa,- but it appears to
be a much larger species, as Dillwyn states the nigosa to be only
ten lines long. It is probably the same species as that represented
by Lister on plates 562 and 563, but I do not find those figures
refered to at all by Dillwyn.

Natica heros. — Shell suboval, thick, rufo-cinereous ; within
whitish ; columella incrassated ; callus not continued over the
upper part of the umbilicus, hardly extending beyond a line drawn
from the base of the collumela to the superior angle of the labrum ;
umbilicus free, simple.

Length about two inches and a half. Inhabits the coast of New
Jersey.

I have two specimens from Great Egg Harbor. It differs from
the preceding species in being less dilated, destitute of the black
line of the apex, and of the much incrassated projection from the
columella so conspicuous in that shell. This is our largest species.
I have a specimen more than three inches in length.

I formerly considered this to be N. rufa, Gmel., but that species
is said by Dillwyn to be only half an inch long, and he refers to
Born, t. 17, f 3, and 4, and also to Lister, Conch, t. 506, f 3,
neither of which figures resemble our species.

87

[J. A. N. S. vol. ii. p. 257, June, 1822.]

Natica pusilla. — Shell thin, suboval, cinereous or rufous,
with sometimes one or two obsolete, dilated, revolving bands ;
columella callous ; callus pressed laterally into the umbilicus,
whitish ; umbilicus nearly closed and consisting only of an arquat-
ed, linear, vertical aperture.

Length about a quarter of an inch. Inhabits the southern
coast. Cabinet of the Academy and Philadelphia Museum.

A small species, generally mistaken for the young of one of the
preceding species.

Thodoxus reclivatus. — Shell thick, strong, globose-oval,
greenish-olive, with numerous, approximate, parallel, irregularly un-
dulated green lines across the volutions ; volutions about three, the
exterior one occupying nearly the whole shell ; spire very short,
obtuse at the apex, and frequently eroded to a level with the supe-
rior edge of the body whirl ; mouth within bluish-white ; labrum
acutely edged ; labium callus, minutely crenated on the edge, and
with a very small tooth near the middle.

Greatest diameter nineteen-twentieths of an inch, greatest trans-
verse diameter four-fifths of an inch. Inhabits East Florida.
Cabinet of the Academy and Philadelphia Museum.

Animal. — Pale, more or less distinctly lineated, or clouded with
black ; foot rounded, almost orbicular, harrdly as long as the shell
is broad; above with four more or less distinct, black, parallel
lines ; rostrum dilated, truncated, tip with four black lines, a black
band connecting the eyes : eyes prominent, appearing to be placed
on a tubercle at the outer base of the tentacula, black with a white
orbit; tentacula with darker or black lines, setaceous, and longer
than the breadth of the rostrum ; beneath immaculate.

I found this species in great plenty, inhabiting St. John's river
in East Florida, from its mouth to Fort Picolata, a distance of one
hundred miles, where the water was potable. It seemed to exist
equally well where the water was as salt as that of the ocean, and
where the intermixture of that condiment could not be detected
by the taste. Its movements are remarkably slow.

88

Class CONCHIFERA.

OsTREA SEMICYLINDRICA. — Stell elongated, semlcylindrie,
white, covered with a fascous epidermis ; sides parallel ; base and
tip rounded, equally obtuse ; inferior valve very convex • superior
valve flat; within white, somewhat perlaceous; muscular impres-
sion large, white.

Length seven-twentieths of an inch. Inhabits the coast of
Greorgia and Florida, imbedded in sponges. Cabinet of the Aca-
demy and Philadelphia Museum.

This species has the habit and manners of the genus. Vidcella,
but differs from it in having very unequal valves and beaks, and
at the same time it differs from the Ostreas in being unattached.
I found several specimens imbedded in sponges, or interposed be-
tween large A&cidia and our common Tliethya, Lam.

Pecten concentricus. — Shell suborbicular, with from eigh-
teexi to twenty elevated, rounded ribs, and very numerous simple
transverse wrinkles ; longitudinal striae none ; one valve somewhat
ventricose, pale-yellow, fasciated concentrically with reddish-fus-
cous or blackish ; the other valve convex, brownish-cinereous ;
auricles subequal ; hinge margin rectilinear in each valve ; within
white.

Length two inches and nine-tenths. Breadth three inches and
one-tenth. Inhabits the coast of New Jersey. Cabinet of the
Academy and Philadelphia Mixseum, and Mr. Hyde's collection.

Var. a. Somewhat more compressed, variegated.

Although this shell is a large species, and is one of our most
common shells, yet I cannot perceive that it has been either figured
or described distinctly in any work to which I can refer. The
inner margin, particularly between the ribs, is sometimes of a dirty
reddish-brown color. I have not seen this species on the southern
coast.

The variety occurs on the coast of New England, and several
specimens are preserved in Mr. William Hyde's cabinet. One
specimen is of a fine bright orange-color, and on one of the valves
only are the concentric bands of blackish ; the margins, which
decline from the beaks, are transversely mottled with white. An-
other has one valve blackish-brown, with about a dozen rather
large white spots on the disk, longitudinally disposed, and white
transverse variegations on the umboncs and beaks; the margins.

89

which decline from the beaks in both valves, are similarly colored ,
and varied with transverse white marks ; the opposite valve is yel-
lowish-white, with the usual bands. It must, however, be observ-
ed, that the epidermis of both these specimens was removed by
muriatic acid. It is probable that the examination of numerous
specimens, will prove this to be a distinct species ; if so, it may be
distinguished by the name of P. horealis.

Pecten dislocatus. — Shell suborbicular, with twenty or
twenty-two elevated rounded ribs, and very numerous concentric
wrinkles ; longitudinal striae none ; whitish, tinged with yellow or
reddish, with a few narrow, transverse, interrupted and dislocated
sanguineous, undulated lines, and five or six pale-reddish, almost
obsolete spots on the margin, at the base of the auricles subequal ;
hinge margin rectilinear in each valve.

Length one inch and a half. Breadth one inch and three-fifths.
My Cabinet.

This is a veiy pretty species, and seems to be confined to the
southern coast, where it is rare. It is very different in its colored
markings from the preceding species, which, however, it much re-
sembles in form. I have a young specimen, on which the red
lines are numerous, but are dilated, pale, and tinted with dull
purplish.

Pandora trilineata. — Shell white, subpellucid, concen-
trically wrinkled ; hinge placed at the posterior slope, which is
very abrupt, and forming a very considerably obtuse angle with
the hinge margin ; hinge margin concavely much arquated, the
surface flattened, and bounded on its edges by two elevated ap-
proximate lines, originating at the beak and continued to the tip,
which is rostrated ; rostrum ascending ; a distinct, slightly impress-
ed line originates at the beaks, and passes to the middle of the
basal margin ; right valve a little convex ; left valve flat.

Length nine-twentieths of an inch. Greatest breadth nineteen-
twentieths of an inch. Inhabits the American coast. Cabinet of
the Academy and Philadelphia Museum.

I first discovered a single valve of this cuiious shell several
years ago at Great Egg Harbor, on the shores of New Jersey ;
since which I have found two or three others on the coast of
Georgia and East Florida, so that it may be said to inhabit our
whole southern and middle coast. The inner edge of the hinge

9

90

margin of one valve, closes over tliat of the other. This species
is very different from the P. msequivalvis, particularly in having
the hinge placed much fixrther back, and consisting of a mere
angle, not prominent ; the rostrum also has a direction more up-
ward.

AviCULA HIRUDO. — Var. Shell perlaceous; epidermis reddish-
brown, with very numerous undulated wrinkles, which are disposed
in radii, and rendered more conspicuous by a white longitudinal
line at the junction of each series of wrinkles with its contiguous
one.

Width about three-fourths of an inch. Inhabits the southern
coast. Cabinet of the Academy and Philadelphia Museum.

It appears to be rare. I have found but a single entire speci-
men, which is young. In its radiating series of wrinkles, it ap-
proximates to A. morio of Leach, but differs from it in magnitude,
and in being radiated with whitish lines. I have a specimen from
the West Indies, which corresponds very well with this, but as it
is a much older shell, it is of a much darker color, and the radii
are interrupted into abbreviated lines.

A valve of an adult shell also occurred on the southern coast,
but so much worn by attrition that its superficial characters are
destroyed.

Mytillus cubitus. — Shell oblong, striated with elevated, sub-
glabrous lines, which are smaller on the anterior side; anterior
edge linear, or slightly concave ; posterior edge ascending from the
base in a right line to a prominent angle, which is rather behind
the middle of the shell, from which it descends by a concave line
to the obliquely and very obtusely rounded tip ; color yellowish,
polished and somewhat facciated with green or brownish, which
disappear on the anterior margin.

Length one and one-fifth of an inch. Breadth half an inch.
Inhabits the coast of the United States. Cabinet of the Academy
and Philadelphia Museum.

This species, seems to bo most closely allied to M. demissiis and
exustus; from the former it is distinguished, by not having the
angle on the posterior side obtusely rounded, and not placed con-
siderably before the middle ; and the line of the edge before this
angle, is not convex as in that shell. It does not at all correspond
with the figures in the Encyc. Method, which are quoted for extis-

91

tm; but it agrees very well, and is probably specifically the same,
with the species represented on plate 365 of Lister's Conch., which
the author thus defines, " musailus parvus, subluteus, leviter stria-
ius."

Mytillus lateralis. — Shell transversely suboval, inflated,
subpellucid, with numerous concentric wrinkles, anterior and pos-
terior margins, longitudinally ribbed with alternate large and small
lines, which crenate the basal margin ; intermediate area destitute
of longitudinal lines ; most prominent part of the shell extending
from the beak to the tip of the anterior margin, and bounded on
its posterior side by an indented line ; epidermis pale-brownish.

Length three-tenths of an inch. Breadth eleven-twentieths of
an inch. Thickness seven-twentieths of an inch. Inhabits the
southern coast. Cabinet of the Academy and Philadelphia Mu-
seum.

Found imbedded in the large Thethya of our coast. This shell
is closely allied to Mytillus discors of Montague.

Mytillus hamatus. — Shell very much contracted and incurved
at the base, which is acute ; valves striated on every part of the
exterior with longitudinal, elevated lines, which are bifid and some-
times trifid towards the tip ; color dark fuscous ; within dark pur-
purescent with a whitish margin.

Length one and one-fifth of an inch. Breadth nearly four-fiflhs
of an inch. Inhabits the Gulf of Mexico. Cabinet of the Acade-
my and Philadelphia Museum.

A common species in the Gulf of Mexico, and is frequently car-
ried to market at New Orleans, attached to the common oyster. It
is remarkably distinct from M. demlssus by the great incurvature
of the beaks, by its inferiority in magnitude, and by having the
strise extending over every part of the surface of the shell.

I cannot refer it to strialulus, with which it seems to have some
affinity, as that species is described to be nearly diaphanous. It
seems to have some affinity with the M. decussatus, Lam., but is
much smaller, and the transverse striae are not very prominent.

MoDiOLA Americana. — Var. Shell oblong, hinge margin ele-
vated in a right line from the beak to the alated angle, from which
it declines also in a right line nearly to an equal distance ; alated
projection rounded; anterior margin short and small ; basal margin

92

with a dilated but slightly impressed contraction in the middle ;
epidermis transversely wrinkled, light-brown, the raised oblique
portion of the shell yellowish-white; cortex with membraneous
scales and filaments, and covering all the anterior portion of the
shell to the beak.

Modiola Americana, Leach. Zool. Misc., vol. 2, pi. 12, fig. 1.
Var.

Inhabits the Southern coast. Length from the tip of the angle
to the middle of the base, three-fifths of an inch nearly. Breadth
one and one-fifth of an inch. Thickness half an inch. Cabinet of
the Academy and Philadelphia Museum.

This variety difi'ers from that figured by Dr. Leach, in being
always destitute of oblique colored radii.

Modiola CASTANEA. — Shell transversely oblong suboval; hinge
margin elevated in a right line from the beak to the alated angle,
from which it declines in a line slightly arquated ; anterior margin
rounded at the tip ; posterior margin rather large ; base with a
dilated but slightly impressed contraction before the middle ; epi-
dermis concentrically wrinkled, castaneous ; cortex not continued
behind the middle of the shell ; within bluish.

Inhabits the Southern coast. Length, from the tip of the angle
to the middle of the base, three-fifths of an inch. Breadth one
and one-tenth of an inch. Thickness nearly half an inch. Cabi-
net of the Academy and Philadelphia Museum.

This species, like the preceding, is furnished with a membrana ■
ceous expansion over a portion of the epidermis, giving rise to a
number of filamentous processes, by means of which the shell is
attached to various marine bodies.

Arca ponderosa. — Shell somewhat oblique, very thick and
ponderous, with from twenty-five to twenty-eight ribs, each marked
by an impressed line ; interstitial spaces equal to the width of the
ribs ; umbones very prominent ; apices remote from each other,
and opposite to the middle of the hinge, spaces between them with
longitudinal lines as prominent as their corresponding teeth ; ante-
rior margin cordate, flattened, distinguished from the disk by an
abrupt angular ridge ; posterior edge rounded, very short ; inferior
edge nearly rectilinear, or contracted in the middle.

Length two inches and one-eighth. Greatest breadth two inches
and a half nearly. Inhabits the Southern coast. My cabinet.

93

A remarkable species and readily recognised.

Arca pexata. — Shell covered with a hairy epidennis, trans-
versely subovate, with from thirty-two to thirty-six ribs, placed
nearer to each other than the lenirth of their own diameters; um-
bones moderate; apices approximate, placed far backward very
near the posterior termination of the hinge ; posterior edge round-
ed, destitute of an angle; anterior edge rounded, with an angle at
the termination of the hinge ; inferior edge regularly rounded.

Length one inch and seven-tenths. Breadth two inches and
three-tenths. Inhabits the coast of the United States. Cabinet
of the Academy and Philadelphia Museum.

A common species, distinguished by the name of the bloody
clam. It is covered with a hairy epidermis, and when violently
opened, an effusion of a red sanies proceeds from the animal. In
the young shell, an angle is perceptible on the posterior edge, at
the termination of the hinge margin^ but this disappears with
age.

Arca incongrua. — Shell somewhat rhomboidal, with from
twenty-six to twenty-eight ribs, placed nearer to each other than
the length of their own diameters, and crossed by elevated, ob-
tuse, equal and equidistant lines, which are altogether wanting on
ten rays of the disk of the left valve ; apices opposite to the middle
of the hinge, distant from each other, with a lanceolate space be-
tween them, of which the breadth is about one-third of its length ;
extremities of the hinge margin angulated ; posterior edge rounded;
inferior edge rounded, that of the right valye extended a little be-
yond the regular curve in the middle ; anterior margin cordate,
flattened ; anterior edge nearly rectilinear.

Length two inches Breadth rather more than two inches. In-
habits the estuaries of the United States. Cabinet of the Academy
and Philadelphia Museum.

This species, which is veiy abundant on our coasrt, strongly re-
sembles A. rhomhea, but agreeably to the figure in the En eye.
Meth., it differs in the width of the space on the hinge margin, in
the width of the spaces between the ribs, and in its more recti-
linear anterior edge.

Arca transversa. — Shell transversely oblong, rhomboidal,-
with from thirty-two to thirty-five ribs, placed at nearly the length
of their own diameters distant from each other ; apices separated

94

by a long narrow space, and situate at the termination of the pos-
terior third of the length of the hinge margin ; extremities of the
hinge margin angulated ', anterior edge, superior moiety recti-
linear ; posterior edge rounded ; inferior edge nearly rectilinear, or
very obtusely rounded ; on the hinge space one or two angulated
lines are drawn from the apex, diverging to the hinge edge.

Length less than seven-twentieths of an inch. Breadth one
inch and one-fifth. Inhabits the coast of the United States. Cabi-
net of the Academy and Philadelphia Museum.

This species which is abundant in some districts, is remarkable
by its transverse form, and may be known among the foregoing
species, by the apex being situate opposite to one-third of the dis-
tance from the posterior termination of the hinge margin.

NucuLA PROXIMA. — Shell sub triangular, oblique, concentrical-
ly wrinkled, and longitudinally marked with numerous, hardly
perceptible striae ; posterior margin very short and very obtusely
rounded, a submarginal impressed line ; anterior margin very ob-
lique, and but slightly arquatcd ; umbo placed far back ; within
perlaceoiLS, polished, edge strongly crenated ; teeth of the hinge
robust, the posterior series very distinct and regular.

Greatest length, parallel with the posterior margin, three-tenths
of an inch. Breadth less than two-fifths of an inch. Inhabits
the Southera coast. Cabinet of the Academy.

Very much resembles TV. nucleus, but is proportionally wider,
and the posterior series of teeth is more regular and distinct. It
may possibly prove to be only a variety, when numerous specimens
are carefully examined and compared.

Venus notata. — Shell obtusely rounded before, and with a
slight undulation on the anterior margin ; disk nearly destitute of
the elevated concentric striae which mark the borders of the shell,
and distinguished by rufous zigzag transverse lines ; within yellow-
ish-white.

Breadth about three inches. Inhabits the coast of the United
States. Cabinet of the Academy and Philadelphia Museum, and
Mr. Wm. Hyde's collection.

A rare species, called the lettered clam. I obtained one speci-
men at Great Egg Harbor, and another on the coast of Georgia.
Mr. Hyde received his specimen from New England ; it has the

95

rufous lines very much dilated, but they still preserve the zigzag
form.

Venus pr^eparca. — Shell subovate, with numerous, elevated,
subacute^ parallel, concentric lines, which subside into mere
wrinkles near the suture of the ligature slope, interstitial spaces
plain ; ligament slope flattened, margined by an acute line ; ante-
rior margin with an obsolete, longitudinal, very obtuse undulation,
which gives the tip of this margin a slightly truncated appearance;
areola cordate, elevated at the suture ; within white or yellowish j
inferior and posterior margins within crcnulated, the crenulae ex-
tending along the edge of the areola to the beak ; in advance of
the anterior termination of the ligament groove of the left valve,
is another distinct groove which receives the edge of the corres-
ponding mai'gin of the other valve.

Width two inches and one-fourth. Inhabits the coast of the
United States. Cabinet of the Academy and Philadelphia Mu-
seum.

This species bears considerable resemblance to V. casina, but
that shell is regularly arquated on the anterior margin in Maton
and Rackett's figure (v. Trans. Lin. Soc. Lond. 8, pi. 2, fig. 1.) It
also approaches V. rigida, but is distinct by its cordate areola, &c.

Venus elevata. — Shell subcordate, longitudinally sulcated,
sulci equal, numerous, dense, on the anterior submargin sparse ;
concentric elevated, remote, lamellar bands ; anterior margin sub-
angulated at tijD ; within, margin crenated, crense obsolete on the
anterior margin, and near the hinge on the posterior margin.

Length four-fifths of an inch. Breadth nine-tenths of an inch.
Inhabits the Southern coast. Cabinet of the Academy.

I obtained but a single bleached valve of this species. It cer-
tainly approaches very near to V. cancellata, but it is distinguish-
ed by being much less obtuse before, and by having the longitu-
dinal striae more numerous. The concentric lamellar bands were
eleven in number on this specimen.

Venus inequalis. — Shell subcordate, longitudinally sulcated,
lines numerous, obsolete on the anterior margin, behind the middle
bifid and alternating with smaller single ones ; concentric, distant,
lamellar bands, but little more elevated than the longitudinal lines ;
anterior margin subangulated ; within, margin crenate, crense obso-

96

lete on the anterior margin and rear 3 the hinge on the posterior
margin.

Length one inch. Breadth one inch and one-fifth. Inhabits
the coast of the Middle States. Cabinet of the Academy and
Philadelphia Museum.

Very similar in form to the preceding, but it is distinguish-
able by the much less elevated and more numerous bands, and by
the bifid, unequal and less numerous longitudinal lines. I have
only found them on the coast of New Jersey and Maiyland.

Venus castanea. — Shell thick and ponderous, suborbicular,
or subtriangular, with prominent and nearly central beaks ; lunule
excavated, lanceolate; cartilage slope rectilinear, indented; valves
with minute concentric wrinkles, and larger waves; epidermis
chestnut-brown, with darker or paler zones ; within white, the
margin very regularly crenulated.

Length one inch. Breadth one inch nearly. Inhabits the
coast of New Jersey. Cabinet of the Academy and Philadelphia
Museum.

A very thick shell, not unfrequent on the coast at Great Egg
Harbor. The surface is often sculptured with very slightly elevated,
obtuse lines, which are sometimes elevated and acute ; it very
closely approximates to Veiius sulcata as figured by Maton and
Eackett, Trans. Lin. Soc. Lond. vol. 8, pi. 2.

Cytherea occulta. — Shell suborbicular, or subtriangular, thick,
with very numerous approximate, obtuse, transverse and longitu-
dinal, elevated lines, which are nearer to each other than the
length of their own diameters, the longitudinal ones not being visi-
ble to the imassisted eye; lunule destitute of the longitudinal lines ;
color yellowish-white with a few large brown spots, luniile and
ligament slope transversely spotted with reddish-brown ; margin
within entire ; anterior cardinal tooth simple.

Length and breadth half an inch. Inhabits the southern shores.
Cabinet of the Academy and Philadelphia Museum.

This shell is very rare, and is not to be mistaken for any other
shell which I have seen on our coast. The aid of a magnifier is
necessary to discover the longitudinal lines.

Tellina alternata. — Shell compressed, oblong, narrowed
and angulated before, white ; numerous parallel, equal, equidistant,

97

impressed concentric lines, which on the anterior margin are alter-
nately obsolete ; interstitial spaces flat ; within tinged with yellow,
a callous line, which is sometimes obsolete, passes from behind
the hinge to the inner margin of the posterior cicatrix ; anterior
hinge tooth emarginate; posterior lamellar tooth very near the
cardinal teeth, so as to appear like a primary tooth, that of the
right valve wanting ; anterior lamellar tooth at the extremity of
the ligament ; anterior hinge slope declining in a somewhat con-
cave line to an obliquely truncated tip.

Length one inch and one-fourth. Width two inches and one-
fifth. Thickness two-fifths of an inch. Inhabits the coast of
Greorgia and East Florida. Cabinet of the Academy and Phila-
delphia Museum.

Rather a common shell, beautifully and very regularly striated.
When cast upon the beach, one of the valves is very commonly
perforated near the hinge ; this operation, it would seem, is most
frequently performed upon the left valve, as, of ten specimens thus
mutilated, I have but two with the perforation on the right valve.
It varies in being destitute of the yellow color within. It is
probably allied to T. punicea, but I have never found it so far
north as the coast of New Jersey. It is much more elongated than
the latter, the striae are far more distinct, and it is entirely and
always destitute of .the rose-colored bands, and lines, such as are
represented in Bern's figure of that shell. It cannot be the 7\
angulosa of Gmel., as that species is described to be suborbicular,
and to have the lateral teeth remote, whereas the alternata has
but one of the lateral teeth remote.

Tellina polita. — Shell transversely subtriangular, minutely
wrinkled concentrically, white, immaculate ; anterior margin rather
shorter than the posterior one, the hinge slope declining, in a very
slightly arquated line, to a subacute termination ; basal margin
nearly rectilinear from behind the middle to the anterior termina-
tion ; a lateral tooth behind the primary teeth.

Length two-fifths of an inch. Breadth thirteen-twentieths of an
inch. Inhabits the southern coast. Cabinet of the Academy and
Philadelphia Museum. Not unfrequently on the beach of South
Carolina and East Florida.

98

[J. A. N. S. vol. ii. p. 302, et seqq., June, 1822.]

Tellin A IRIS. — Shell very thin and fragile, pellucid, compressed,
transversely oblong-suboval, iridescent, white, with generally a
rosaceous disk and one or two anterior rays, with numerous minute
concentric wrinkles, and minute, oblique, acutely impressed, equi-
distant striae crossing them ; striae abbreviated before and not at-
taining the anterior margin, which is narrowed and subacute : basal
edge rectilinear opposite to the beaks.

Length more than three-tenths of an inch. Breadth more than
eleven-twentieths of an inch. Inhabits the southern shores. Cabi-
net of the Academy and Philadelphia Museum.

A beautiful little species, very remarkable by the oblique course
of the striae. It is rather common.

Tellina flexuosa. — Shell suborbicular, white ; anterior mar-
gin longer than the posterior one, and less obtusely rounded ; beak
placed behind the middle, not prominent ; surface obliquely sculp-
tured with very regular, parallel, impressed lines, which, on the
anterior margin, are four or five times refracted and infracted alter-
nately ; longitudinal striae none ; transverse wrinkles minute.

Length nine-twentieths of an inch. Breadth rather more.
Thickness one-fourth of an inch. Inhabits the southern coast-
Cabinet of the Academy and Philadelphia Museum.

The fold on the anterior margin is very slight, but perceptible,
and is rendered remarkable by the zigzag course of the oblique
striae over it.
■ Tellina tenera. — Shell very thin and fragile, pellucid, com-
pressed, transversely oblong-suboval, whitish, iridescent, concen-
trically wrinkled ; basal edge arquated, not rectilinear opposite to
the beaks ; hinge teeth two, larger one emarginate ; posterior tooth
but little elevated ; anterior tooth obsolete ; beak placed behind
the middle.

Length three-tenths of an inch nearly. Breadth half an inch.
Inhabits the coast of New Jersey. Cabinet of the Academy.

Very much resembles T. iris, but is destitute of the oblique
striae which are so ornamental to that species, from which it also
differs in being arquated on the whole length of the basal edge.
It was discovered by my brother Mr. Benjamin Say, near Great
Egg Harbor.

99

PsAMMOBiA LUSORiA. — Shell transversely, oblong-subovalj
oluish-whitc, witli minute transverse wrinkles ; apex rather nearer
the anterior end ; anterior margin narrowed, inclining to the left
at the end and gaping ; cartilage slope rectilinear, with an obtuse,
obsolete, convex line on the left valve.

Length three-fifths of an inch. Breadth one inch. Inhabits the
Southern States. Cabinet of the Academy and Philadelphia Mu-
seum.

This shell does not appear to be very common. It seems to
vary in having often two teeth on each valve, as in Sanguinolaria.

DoNAX VARIABILIS. — Shell triangular; anterior margin ob-
liquely truncated, cordate, suture a little convex ; posterior hinge
margin nearly rectilinear, suture indented ; base a little prominent,
beyond a regular cui-ve, near the middle ; valves longitudinally
striated with numerous, equal, parallel, regular, impressed lines,
hardly visible to the unassisted eye, and obsolete on the posterior
margin ; basal edge within crenate.

Length half an inch. Width nine-tenths of an inch. Thick-
ness seven-twentieths of an inch. Inhabits the coast of Georgia
and East Florida. Cabinet of the Academy and Philadelphia Mu-
seum.

Varies very much in color and is a very pretty shell. Its usual
varieties are red, white, yellow, or elegantly radiated with dilated
reddish-brown lines, upon a white or yellow ground ; lines are pur-
purescent within the shell. A veiy common shell ; I found it
more particularly numerous on the beach of Cumberland island,
where, in favorable situations, at the recess of the tide, it may be
taken up in handfuls, without any intermixture of sand. It is
very distinct from D. rugosa, but approaches much nearer to D.
trunculus, from which it is distinguished by being more abruptly
truncated before, smaller, and the longitudinal lines are more in-
dented. I have no doubt but this species has been regarded, by
authors, as the same with trunculus, if so, judging by an individual
of that species in the collection of the Academy, at least two dis-
tinct species have been confounded together under that common
name.

DoNAX POSSOR. — Shell subtriangular ; anterior margin short and
rounded ; posterior hinge slope rectilinear ; base very slightly
prominent beyond a regular curve at the middle; valves longitudi-

100

ually striated with numerous, equal, parallel, regular impressed
Hues, not visible to the unassisted eye, and obsolete on the poste-
rior margin ; basal edge within crenate ; color pale-livid, with two
longitudinal whitish rays before the middle, both within and with-
out.

Var. a. Whitish. Var. I. Yellowish. Breadth from half an
inch to three-fifths. Inhabits the coasts of New Jeraey and Mary-
land. Cabinet of -the Academy and Philadelphia Museum.

Very numerous under the surface of the sand, which is exposed
at the recess of the tide. A wave, by removing the surface of the
sand, exposes a great many individuals to view, at its refluence ;
these immediately penetrate the sand, and before the recurrence of
the surge they are concealed.

They are preyed upon by several shore birds and fish ; the drum
(^Scisena chromii) and sheep's-head (Sjmrns ovicejfhalus) are
sometimes caught in the surf in considerable numbers, whilst in
pursuit of them.

Amphidesma orbiculata. — Shell orbicular, somewhat com-
pressed ; beak nearly central, and a little prominent ; posterior
slope a little concave near the beak ; lunule small ; valves slightly
wrinkled transversely } ajiterior submargin with an obsolete very
obtuse undulation, and with a few longitudinal obsolete lines ;
color dirty white ; hinge with two lamellar teeth, the posterior one
placed near to the primary tooth, and shorter than the anterior
one ; interior ligament cavity profound, fusiform, parallel with the
anterior slope, originating at the extreme tip of the beak, and ter-
minating nearly opposite to the middle of the anterior lamellar
tooth.

Length one inch and one-tenth. Breadth one inch and one-
tenth. Inhabits the coast of Georgia. Cabinet of the Academy
and Philadelphia Museum.

Appears to be a rare species ; the largest I have seen is one inch
and two-fifths in bread tli.

Amphidesma .^qualis. — Shell orbicular, slightly oblique,
polished, white, witli very minute and numerous concentric
wrinkles near the margin, which are obsolete on the disk and
umbo ; lateral teeth none ; primary teeth two in the left valve and
one in the other ; interior ligament cavity subfusiforni, as long as
the exterior ligament.

101

Length two-fifths of an inch. Inhabits the southern coast. Cabi-
net of the Academy and Philadelphia Museum.
A small species, not very commonly found.
Ampiiidksma punctata. — Shell orbicular, white, with very
minute, numerous, concentric wrinkles, and very minute, numerous
punctures ; lateral teeth none ; primaiy teeth two in each valve, of
which one has a deep groove, which gives it a bifid appearance ;
groove of the interior cartilage not very distinct; within a small
projecting rim or elevated line near the edge extends from the
hinge to the basal margin.

Length about seven-twentieths of an inch. Breadth mucli the
same. Inhabits the southern shores. Cabinet of the Academy.

This shell bears a strong resemblance to the preceding, on an
exterior and transient view of its valves ; but on examination it
will be perceived to be more orbicular and less oblique, and that
the surface is less polished. By the aid of a magnifier, the surface
will be observed to exhibit a remarkable punctured appearance.

Mactra SIMILIS. — Shell subtrigonate, smooth, or very slight^
wrinkled, white on the disk or upon the umbones, and dirty light
brownish color on the margin ; umbones nearly central ; lateral
teeth strongly and regularly crenated on the side next the recipient
cavity.

Length one inch and three-twentieths, nearly. Width one inch
and two-fifths. Inhabits the coast of the United States. Cabinet
of the Academy.

The specimens which I obtained from the coast of New Jersey
seem closely allied to Var. a. of 31. solida as presented on pi. 258,
fig. 1, of the Encyc. Method., the proportions of the difi"erent parts
of the shell nearly corresponding with those of that figure. But
upon comparing it with several specimens of M. solida sent to the
Academy by Mr. O'Kelly of Ireland, I find its proportions to be
altogether different, being longer and not so wide.

Mactra lateralis. — Shell triangular, very convex, of a
smooth appearance, but with very minute, transverse wrinkles ;
lateral margins flattened, cordate, with a rectilinear, sometimes
concave profile, one margin rounded at the tip, the other longer
and less obtuse ; umbo nearly central, prominent.

Length half an inch. Breadth thirteen-twentieths of an inch.
Thickness seven-twentieths of an inch. Inhabits the coast of the

102

United States. Cabinet of the Academy and Philadelphia Mu-
seum.

A very common shell on almost all parts of our coast.

Mactra oblonga. — Shell transverse, oblong-oval ; very slightly
wrinkled, excepting upon the margin ; umbo hardly prominent ; two
strong distant lines or folds drawn from the apex to the anterior
extremity of the shell ; color dull whitish, hardly polished, umbo
slightly tinged with ferruginous, within white, highly polished.

Length nine-twentieths of an inch. Breadth one inch and
nine-tenths. Inhabits the coast of Greorgia. Cabinet of the
Academy and Philadelphia Museimii.

Of this species I found but three valves, on one of the sea
islands of Greorgia.

Lutraria lineata. — Shell transversely suboval, thin white,
tinged with ferruginous; posterior hiatus patulous, anterior one
linear and commencing below the hinge slope ; hinge slope with a
rectilinear profile, and flattened, oblong-sub cordate surface ; valves
unequally wrinkled ; posterior margin rounded, short, with a re-
fleeted edge, and submarginal carinated line ; within undulated,
anterior margin glabrous, and with an indented submarginal line
corresponding with the exterior carinated one.

Length one inch and nine-tenths. Width two inches and seven-
tenths. Thickness one inch and one-twentieth. Inhabits the
coasts of Georgia and East Florida. Cabinet of the Academy and
Philadelphia Museum.

Not uncommon on the southern coast, and may be readily dis-
tinguished by the carinated line on the posterior submargin.

Lutraria canaliculata. — Shell transversely oval-orbicular,
very thin and fragile, white, inflated j valves equally, concentri-
cally, and regularly grooved, very feint parallel lines within the
grooves ; posterior margin short, subcuneiforni, compressed ; a mar-
ginal, longtudinal, irregular, subimpressed line, between which
and the edge the grooves become mere wrinkles ; posterior slope
subrectilincar, hiatus considerable ; anterior margin regularly
curved, the slope convex ; within grooved as without, anterior
angle glabrous.

Greatest length two inches and one-tweutieth. Breadth two in-
ches and a half. Thickness one inch and one-fourth. Inhabits
the coast of the United States. Occurs on the coast of Maryland

103

and as far south as East Florida. Cabinet of the Academy and
Philadelphia Museiim.

Yeiy distinct from the preceding species, and probably approaches
L. crassiplica of Lamarck.

CoRBULA CONTRACTA. — Shell transversely subovate; valves
subequal, regularly and profoundly striated transversely ; beaks
not prominent, nearly central, one side rounded and the other sub-
acute ; basal margin contracted near the middle, and one half of
the length of the edge of one valve concealing one half of the
edge of the opposite valve.

Length one-fourth of an inch. Breadth two-fifths of an inch.
Thickness one-fifth of an inch, nearly. Inhabits the coasts of
Georgia and East Flarida. Cabinet of the Academy and Phila-
delphia Museum.

I found two specimens of this shell. The strige are precisely
similar to those of the larger valve of Mi/a irisequivalvis of Mon-
tague ( C. nucleus of Lam.)

Mya acuta. — Shell oblong-subovate, narrowed behind, rather
strongly wrinkled ; posterior hinge margin and posterior basal mar-
gin subequally arquated ; tip of the posterior margin equidistant
from the apex and middle of the base ; tooth moderate, with a
small, not prominent, tooth on its posterior side.

Length one inch and a half. Breadth two^^inches and four-fifths.
Inhabits the southern coast. Cabinet of the Academy and Phila-
delphia Museum.

I have but two valves, which are old and bleached. It resem-
bles M. arenaria, but is much smaller at the posterior termination,
than the con-esponding part of that shell, as figured by Bruguiere.
One of the valves alluded to is more than four inches in breadth ;
it corresponds very well in the outline with Pennant's fig. of
arenaria. My decorticated specimens have an obsoletely radiated
appearance.

Mya mercenaria. — Shell subovate, convex, somewhat un-
equal, transversely wrinkled; posterior hinge margin curving
abruptly downward to the tip of the posterior margin, which is
much nearer to the middle of the base than to the apex; tooth
robust, prominent, very convex within, and with a small tooth on
its posterior side ; within white.

104

Length one and three-tenths of an inch. Breadth two inches.
Inhabits the coast of the United States. Cabinet of tbe Academy
and Philadelphia Museum.

This species, as well as the preceding, is known by the name
of the Maninose or Piss clam, from the circumstance of its occa-
sionally ejecting a sudden jet of water, to a considerable height
above the surface of the sand, during the refluence of the tide.
This jet may be commanded by stamping upon the sand with the
footj near the entrance of their dwelling ; it is sometimes brought
to our markets, and is by many persons highly esteemed as food ;
it is said by some to be preferable to the common clam, ( Venus
mercenaria.^

Anatina papyratia. — Shell turgid, very thin and fragile?
transversely ovate, one valve very convex, and at the basal margin
projecting a little beyond the edge of the other ; beaks not pro-
minent, placed near one end ; surface of the valves very slightly
wrinkled, white ; shorter margin a little gaping, and with a longi-
tudinal wave ; tooth very oblique.

Inhabits the southern coast. Length two-fifths of an inch.
Width thirteen-twentieths of an inch. Thickness one-fourth of
an inch. Cabinet of the Academy and Philadelphia Museum.

This species does not appear to be very common.

SoLEN costatus. — Shell transversely elongate-oval, concen-
trically wrinkled, very much compressed, very thin and fragile,
rounded at each end ; hinge nearly equidistant from the posterior
termination of the shell and the middle of the hinge margin •
teeth two, sometimes none, in each valve, the posterior one upright,
the other inclining forward ; g, strong, broad, elevated line within
passes from the hinge towards the base and becomes obsolete near
that part ; color pale violaceous, with about three whitish rays.

Breadth one inch and a half. Inhabits Grreat Egg Harbor, New
Jersey. Cabinet of the Academy.

Rather rare, I have obtained but few and incomplete specimens.
The internal costa is somewhat similar to that of S. Icgumen, but
it is much more elongated, and does not incline obliquely forward,
as in that shell ; it probably approaches nearest to S. minumus of
Tranqucbar.

SoLEN CENTRALIS. — Shell transvcrscly oblong-oval, slightly

105

wrinkled concentrically, compressed, fragile, rounded at each end ;
hinge central, teeth two in the left valv§ and one in the right ;
epidermis pale yellowish-brown ; a broad, obsoletely elevated line
within passes from the hinge towards the base, and terminates
beyond the middle.

Length half and inch. Breadth one inch and three-tenths.
Inhabits the southern shores. Cabinet of the Academy and
Philadelphia Museum.

Somewhat rare. It has very much the appearace, at first sight,
of the young of S. carabseus, but it cannot be mistaken for it, as
the teeth of the hinge are invariably central, whilst those of that
species are anterior to the centre, and the interior of the shell of
that species has never the slightest appearance of a costa.

SoLEN viRiDis. — Shell fragile, elongated, compressed, a little
narrowed before, slightly wrinkled concentrically, the wrinkles
regularly rounded towards the extremity; hinge margin nearly
rectilinear ; basal margin a little arquated ; anterior tip rounded ,
posterior tip obliquely truncated, a little reflected, and rounded
near the base ; hinge terminal ; teeth one in each valve, each
having a flattened vertical surface, which turns upon that of the
opposite tooth ; epidermis pale green.

Length nine-twentieths of an inch. Breadth two and three-
twentieths of an inch. Inhabits the southern coast. Cabinet of
the Academy and Philadelphia Museum.

A common shell. The hinge is formed upon the same plan
with that of the ;S'. vagina and tnmcatus, but it differs from
those species, in being much more rounded at each extremity,
and in being narrowed at the anterior tip. I think it probable,
however, that this species has been regarded as a variety of &'■
truncatus.

SoLEMYA VELUM. — Shell remarkably thin and fragile, trans-
versely-oblong, rather longer at the posterior end ; hinge edentulous,
placed near the anterior end, with a slightly prominent cartilage,
and an interior elevated callus, which is fornicated beneath ; valves
radiated with about fifteen double lines, which are sparse towards
the middle of the valves ; epidermis pale yellowish-brown, extend-
ing much beyond the basal and lateral edges of the valves, and at
the hinge margin, connecting them together nearly the whole

10

106

length of the shell ; within hluish-white ; umho destitute of the
slightest elevation ; anterior and posterior margins rounded; supe-
rior and inferior margins rectilinear, parallel.

Length seven-twentieths of an inch. Breadth nineteen-twen-
tieths of an inch. Inhabits the southern coast. Cabinet of the
Academy.

Occurs sometimes cast on shore, generally in fragments, but is
by no means a common shell.

Saxicava distorta. — Shell thick, inequal, rugged, trans-
versely oblong-subovate ; epidermis pale-brownish, much wrinkled ;
umbo prominent, placed very far back ; posterior margin rounded,
generally very short; anterior margin often truncated, with a
prominent ridge passing from its inferior angle to the beak.

Length about three-fifths of an inch. Width about one inch.
Inhabits the southfi-n coast. Cabinet of the Academy and Phila-
delphia Museum.

When young, it is generally more or less contracted near the
middle of the basal margin, but this character decreases as the
shell increases in size, until it disappears entirely in the adult
state. It is in other respects variable in form and proportion, the
beaks are rarely placed so far back as to be parallel with the tip of
the posterior margin ; it much resembles Mi/tillus rugosus of Lin.,
but appears to be a much thicker shell. It is generally imbedded
in our large Thethya, Lam., and not imfrequently intervenes
between the substance of the Tlicthya and the sides of a large
Ascidia, which also attaches itself to that animal. It is also
sometimes found in a species of spongia. Pinnotheres hi/ssomm
of this Journal, inhabits this shell. The young shell is furnished
with a prominent incrassated hinge tooth, which closes into a cor-
responding depresssion in the opposite valve ; but this tooth dis-
appears with age.

It is referrible to the genus Pholeohm of Leach.

Petricola fornicata. — Shell transversely elongated, posterior
side very short ; anterior side a little gaping ; hinge and basal mar-
gins subparallel ; valves longitudinally radiated with elevated lines,
which, anterior to that which terminates at the middle of the base,
arc alternately more or less prominent, filiform, and all posterior to
that line are fornicated costa ; concentric wrinkles numerous, more
remarkable on the anterior margin ; lunule ovate-acute, simply

107

sculptured with the concentric wrinkles; within radiated with
strongly indented lines, which, on the anterior margin, arc obso-
lete; teeth two, rarely three, on each valve, one of which is bifid
at tip or grooved on the inner side, and the other usually not
prominent above the margin.

Length three-fifths of an inch. Width one inch and seven-
tenths. Thickness eleven-twentieths of an inch. Inhabits the
coast of North America. Cabinet of the Academy and Philadel-
phia Museum.

This shell, which has very much the aspect of a Pholas, is not
uncommon, but is more abundant on the southern coast. It ap-
proaches F. plioladiformis of Lamarck, but diflfers in not being
" subglabrous before."

Pholas oblongata. — Shell thin, white, transversely much
elongated ; basal and hinge margins nearly parallel ; anterior and
posterior margins rounded ; valves transversely and longitudinally
striated, the stride muricated and elevated on the anterior side into
costae, which are more prominently and densely muricated ; hinge
callus polished, minutely striated transversely and longitudinally,
and with about twelve cells, anterior to which is a recurved mar-
gin of the shell, forming a cavity; dentiform process dilated, in-
curved, spoon-shaped, emarginate on the posterior side, and irregu-
larly truncated at tip.

Grreatest length, one and one-fifth. Breadth, four inches and
two-fifths. Inhabits Georgia, Carolina, and East Florida.

Very common on the southern coast, penetrating compact mud
or clay. Small clods of this clay are often rolled ashore by the
waves, either containing this species, or exhibiting proofs of hav-
ing been its habitation, by the numerous perforations with which
they are distinguished. In many places, where a bed of this mud
is barred by the refluent tide, these shells may be seen in consider-
able numbers, with a portion of the smaller side appearing above
the surface. It is proportionally broader than the shell figured by
Lister, plate 423, and it seems to be allied to P. campechensis.

Pholas truncata. — Shell white, transversely oblong, sub-
pentangular ; anterior margin rostrated, obtusely cuneiform in the
middle ; posterior margin broadly truncated at tip ; valves trans-
versely wrinkled and longitudinally striated, muricated, particularly
on the anterior side, with small erect scales, which are not arched

108

beneath ; posterior margin, from a line extending from the beak to
the inferior angle of the truncature, destitute of the striaj and
mutic ; hinge callous, formed of the duplicature of the hinge mar-
gin, and destitute of cells, a small tooth upon the inner margin,
projecting backward ; dentiform process cui-ved, prominent, slender,
flat.

Length three-fourths of an inch. Breadth one inch and seven-
tenths. Inhabits the southern coast. Cabinet of the Academy
and Philadelphia Museum.

A common shell. Pennant, in his observations upon P. parva,
says, " I have a piece (of wood) filled with them, which was found
near Pensacola, in West Florida." May this not have been the
young of our truncafa ; or have we in reality the jmrva to add to
our catalogue ? Pennant's figure (volume iv. British Zool., pi. 40,
fig. 13,) of that species does not represent a truncature at the pos-
terior side of the shell ; otherwise ours might be supposed to be a
variety of it, although it attains to a much larger size.

Pholas cuneiformis. — Shell subcuneiform ; anterior margin
. nearly closed, transversely truncated from the hinge ; the surface
transversely striated in an undulated manner, with elevated,
minutely crenate lines ; the interstitial lines smooth ; these lines
partially interrupt a profoundly impressed longitudinal sulcus,
which passes from the beak to near the middle of the base ; the
inferior portion of this margin is destitute of striae; posterior margin
attenuated by nearly rectilinear edges, to a rounded tip ; surface
transversely wrinkled ; hinge callous, composed of the reflected mar-
gin, which forms a cavity before, and is destitute of cells ; denti-
form process incurved, slender, filiform ; hinge plate ovate-trian-
gular, with a short projecting angle on the anterior middle, and
subacute behind ; within, disk slightly contracted by an elevated
line corresponding with the external sulcus.

Length nine-twentieths of an inch. Width four-fifths of an inch.
Inhabits the southern coast. Cabinet of the Academy and Phila-
delphia Museum.

Is often cast ashore in old wood, which it penetrates. It bears
some resemblance in form to the shell represented in the Encyc.
Method., t. 170, fig. 5, &c. Its longitudinal sulcus is very similar
to that of P. crispata, but in many other respects it is closely al-
lied to P. pimllus, and like that species it is distinguished by two

109

eloagated lamellar plates, which cover the sutures of the posterior
junction of the valves.

Type and Class ANNULOSA CIRllIPEDES.
Family BALANIDEA.

OoNOPEA. — Shell sessile, fixed, composed of two coacs joined
by their bases, the lines of junction earinate each side; inferior
cone entire, attached by its anterior side and tip to marine bodies ;
superior cone formed of six united pieces, with an aperture at the
summit, closed by a quadrivalved operculum.

CoNOPEA ELONGATA. — Shell elongated before and behind into
compressed processes ; posterior valves of the operculum more
prominent and truncated at tip.

Inhabits the southern coasts on Gorgonia vh-gulata, Lam.
Cabinet of the Academy and Philadelphia Museum.

Anterior and posterior processes very much compressed, acutely
edged above and beneath, and usually as long as the body of the
shell; shell generally covered with a dirty brown epidermis, be-
neath which it is white, with rufous clouds and lines ; posterior
valves of the operculum larger, more prominent, truncated or
widely emargimate at tip.

Balanus galcatus, an inhabitant of the Asiatic ocean, a species
long known, and described by various authors, is congeneric with
the species here described. The peculiar characters of these
shells, their general appearance and their habitat will not admit
of their being refeiTed to the genus Balanus in a perfectly natural
arrangement. I have therefore thought it necessary to frame the
present genus for their reception.

The anterior process of the elongata is generally acuminated and
longer than the posterior one, which is more compressed, and is
generally more or less elevated from the branch of the Gorgonia,
upon which the anterior process and the basal cone are firmly at-
tached.

Bruguiere informs us that the galea is obtained from great
depths in the ocean only ; but I have found the elongata in con-
siderable numbers in inlets of the bay of Charleston, on Gorgonia,
which at the recess of the tide was visible on the surface of the
water.

no

This species, like the galta, is often found coated over with the
oordcal envelope of the Gorgonia, and the animal destroyed, pro-
bably by its encroaehinent.

CoROxrLA DEMrLATA. — SheU depTessed-conic; base oval:
height equal to about one-third of the base ; valves and interstice--
smooth, the anterior valve largest, and the posterior one smallest ;
operctdum transversely striated, the p>Osterior pair of valves with :*
submaiginal impressed line, from ^hich to the edge are drawn
three or four other impressed lines.

Found on the clypeus of Limuhis Polyphemus. CoUeetion o:
the Academy and Philadelphia Museum.

The posterior margins of the posterior valves of the operculum,
are divided by the impressed lines into three or four broad, flat.
dentiform divisions, which, however, but simply crenate the edge

[J. A. N. S. Vol. ii. p. 378, et seqq. Dec. 1S22.]

LriiXTTS HUjniJS. — Shell ovate-conic, thin, translucent, with
slight wrinkles ; volutions nearly sis, convex, terminal one very
minute ; suture well indented ; aperture about equal in length tc
the spire; labium with an obvious plate of calcareous deposit; a
distinct and rather open umbilical aperture ; color pale reddish-
white or yellowish-white.

Total length seven- twentieths. Inhabits South Carolina.
Of a dozen specimens sent me by 3Ir. Elliott, none exceeded
the limit here assigned to the species. It differs much from any
other species I have seen ; a variety of it, sometimes quite black,
•was found by Dr. M"Euen at Oswego, on the Susquehanna.

It may be useful here to remark that, in consequence of a typo-
graphical error in the first part of the second volume of this work,
the species above described may be confounded with the de^iJiosu*.
The length of that shell is erroneously stated to be seven-twentieths
of an inch, instead of seven-tenths, its true length.

Paludixa graxa. — Shell conic-ovate; whorls not perceptibly
wrinkled, convex ; suture deeply impressed ; aperture orbicalar,
hardly angulated above ; labium with the superior edge appressed
to the surface of the penultimate volution ; umbilicus rather small,
profound.

Length less than one-tenth of an inch. Inhabits Pennsylvania.

Ill

This very small species is found in plenty in the fish ponds at
Harrowgate, crawling on the dead leaves which have fallen to tlio
bottom of the water. It resembles P. lustrica, but is a smaller,
less elongated shell, and the superior portion of the labium is not
an unaltered continuation of the lips as in that shell, but is ap-
pressed to the surface of the penultimate whorl in the usual manner
of calcareous deposition upon that part.

Melania catenaria. — Shell conic, blackish ; whorls seven or
eight, slightly undulated transversely, and with eight or nine re-
volving, elevated lines, the four or five superior ones of which are
almost interrupted between the undulations.

Length less than half an inch. Inhabits South Carolina.

The essential specific character resides in the catenated appear-
ance of the superior revolving lines of the whorls, resulting from
their being more prominent on the undulations which they cross,
than between them, where they are often obsolete. This species
was sent to me by Mr. Stephen Elliott, who obtained it in lime-
stone springs, St. John's, Berkley.

Melania multilineata. — Shell gradually tapering; apex
generally much eroded ; whorls about seven, a little convex, with
numerous, filiform, elevated, subequal lines, which are from ten to
twenty in number on the body whorl.

Length nineteen-twentieths ; greatest width two-fifths of an
inch. Inhabits tributaries to the Delaware.

I found several specimens of this shell in Frankford Creek j and
Professor Vanuxem presented me with others which he obtained
from a creek in New Jersey. The M. elevata, (p. 176 of this
work,) from its attributed specific characters, might be supposed
to be nearly related to this shell, but it difi"ers in being of a more
accurate conic form, the whorls being flattened, and not convex as
in this species ; its raised lines are also few in number.

Cyclas rhomboidea. — Shell transversely orbicular-rhombi-
form, subequilateral, pale, with elevated somewhat regular trans-
verse lines ; umbo not prominent.

Breadth more than one-fourth of an inch. Inhabits lake Cham-
plain.

It is probable that this species attains to a somewhat larger size
than the two specimens from which the above description was

112

taken, and which were found by Mr. Augustus Jessup. It is

distinguishable from C. similis by its more rhomboidal form.

Cyclas partumeia. — Shell thin and fragile, transversely-sub-
orbicular, with small, irregular, inequidistant, concentric wrinkles,
and larger adventitious undulations; base rounded; anterior and
posterior edges nearly central ; hinge teeth prominent and distinct ;
lateral teeth prominent, white ; within impressed by the exterior
undulations, and bluish-white on the margin and submargin.

Length nine-twentieths; breadth eleven-twentieths of an inch.

This species was found by Mr. William Hyde, in a pond near
(lermantown, in plenty. In comparison with C. similis, it is
thinner, more transparent, not flattened at base, more obtusely
rounded each side, and instead of grooves of some degree of regu-
larity as in that shell, it is sculptured with irregular wrinkles and
waves. Mr. Hyde took fifty young ones out of a single specimen-

N. B. The genus Cyclas was inserted into this essay inad-
vertently ; the species, however, are new.*

[*The title of the paper being " Description of Univalve, &c., Shells.
—Ed.]

[J. A. N. S. vol. iv. p.. 368, et seqq., 1825.]

MoDiOLA. — Amongst a number of marine shells from the island
of Minorca, presented to the Academy by Dr. Alexander Mont-
gomery, of the U. S. Navy, is a single valve of the Pecten nodosus,
Linn., on which were several elevations that, on a cursory glance,
presented an appearance not unlike the Balanus. On a more par-
ticular inspection, each elevation proved to be similar to the others
in form and consistence, and to be composed of fine dark colored
sand, agglutinated together, attached by a broad base to the surface
of the Pecten, and rising in the shape of a very low cone around
an included shell, the visible portion of which is exactly cordate.
Having carefully detached the mass, I found the imbedded shell
to be a Modiohi, closely allied to the discors, Gmel., with its byssus
very firmly aflixed to the supporting surface.

The following is a description of this shell :

MoDiOLA OPIFEX. — Oval, reddish-brown; anterior hinge-mar-
gin flattened, cordate ; within iridescent.

Base contracted behind the middle, the contraction not wide

113

QOr very deep ; between this part and the beaks tbe surface is
blackish and transversely wrinkled ; posterior and anterior surface
of the valve longitudinally striated, with the exception of the an-
terior cordate hinge-margin, which is flattened and covered by a
thick stratum of compact sand ; anterior tip equally arcuated above
and below j within iridescent, brilliant, striated as on the exterior
surface, edge crenate.

Breadth nearly half an inch ; length more than one-fifth of an
inch.

This species differs from the if. discors, and M. lateralis, nob.,
not only by its very singular habit, but also by its flat and per-
fectly heart-shaped anterior margin ; the regular and equal curva-
ture of its anterior extremity ; the narrower interval between the
anterior and posterior striated surfaces, and the more profound and
less dilated basal contraction.

PI. xix. fig. 2. M. opifex imbedded in its mound, a. External view
of a valve, b. Internal view of a valve, (all enlarged.)

[Included on pi. 70.— Ed.]

[J. A. N. S., vol. V. p. 122, et seqq., Sept. 1825.]

Lymneus modicelles. — Shell blackish, not elongated : whorls
rather more than four, convex ; suture deeply impressed; apex
acute ; aperture very regular, the labium and labrum being sub-
equally curved ; the fold of the columella rather slight.

Total length seven-twentieths of an inch ; breadth one-fifth ;
length of the aperture one-fifth.

Smaller than any of the species I have hitherto described. It
was found by Dr. M'Euen at Oswego, on the Susquehanna river
near the State of New York.

Lymneus obrussus. — Shell oblong, rather slender, pale yel-
lowish testaceous ; whorls five, slightly rounded ; apex acute :
suture deeply impressed ; aperture not dilated, within pure white j
columella with the sinus of the fold very obvious.

Lister, pi. 114, f(]i. 8 ?

Total length nine-twentieths of an inch ; aperture one-fourth ;
breadth nearly one-fifth.

All the individuals that have occurred were covered with an
earthy slime. They inhabit a small rivulet below the fish-ponds
at Harrowgate, the seat of my friend Mr. J. Gilliams.

114

Lymneus pinguis. — Shell oval, rather ventricose, pale, dirty
yellowish ; whorls nearly four, rapidly diminishing to the apex,
which is dull fulvous ; suture moderate ; spire rather more than
half the length of the aperture; aperture large; labrum with the
inner margin a little thickened.

Total length eleven-twentieths of an inch; aperture rather more
than seven-twentieths ; .breadth seven-twentieths.

Proportionally shorter and much more dilated than other species
of the country, with the exception of L. macrostomus, nob., from
which it is readily distinguished. It inhabits the Delaware and
Schuylkill rivers near Philadelphia, in company with L. catasco-
pium, nob.

Lymneus galbanus. — Shell subovate; whorls nearly five,
very convex; suture very deeply impressed; apex acute; body
whorl a little flattened in the middle ; aperture not dilated ; colu-
mella with the sinus of the fold very obvious.

Length three-tenths of an inch : aperture rather more than half
the whole length.

For this shell I am indebted to Mr. Nuttall, who obtained it in
a marl pit near Franklin, New Jersey. He considers it fossil, as
well as numerous specimens of Planorhls campanulafus, Valvata
tricarinata, and Phyi>a heterostropha, found with it. I have never
seen a recent specimen, but the present corresponds with some in-
dividuals belonging to the Philadelphia Museum, also said to be
fossil.

PiiYSA ANCILLARIA. — Shell heterostrophe, subglobose, pale yel-
lowish; whorls rather more than four, very rapidly attenuated ;
spire truncated, hardly elevated beyond the general curve of the
surface; suture not impressed; aperture but little shorter than
the shell, dilated ; labrum a little thickened on the inner margin.

Length more than one-half of an inch.

The spire of this species is unusually short, truncated at tip
like the Paludina decisa, nob. ; and the suture is so inconspicu-
ous as to give rise to the name which I have chosen for it. My
brother, B. Say, obtained it in the Delaware river near Easton,
and Mr. Jessup collected numerous specimens in the Connecticut
river, above Hartford. It may be distinguished from P. hetero-
stropha, nob., by the shorter and truncated spire, inconspicuous

115

suture, as well as by the more obtusely rounded junction of the
labruni with the base, and by the general form.

Paludina subglobosa. — Shell subglobose ; whorls three and
a half, much rounded, rapidly enlarging j suture profoundly im-
pressed ; aperture subovate ; umbilicus very narrow, nearly closed
by the labrum ; spire very short, convex.

Inhabits the North-western Territory. Length less than three-
tenths of an inch.

I obtained this shell when traversing the North-western part of
the Union. It is much larger than the porata, nob., which it re-
sembles considerably, but its whorls are much more rapidly en-
larged, and the umbilicus is much narrower.

Melania simplex. — Shell conic, blackish, rather rapidly at-
tenuated to an acute apex ; suture not deeply impressed ; volutions
about eight, but little rounded ; apertute longitudinal ; within
dull reddish ; labrum with the edge not undulated, or but very
slightly and obtusely so near the superior termination.

Length three-fifths of an inch ; greatest breadth three-tenths.

For this species we are indebted to Professor Vanuxem, who
presented several specimens to the Academy. He informs me
that he obtained them in Virginia, in a stream running from Ab-
ingdon to the Salt Works, and from the stream on which General
Preston's grist-mill is situated, near the Salt Works, as well as in
a brook running through the salt water valley, and discharging
into the Holstein river. Near the summit the whorls are marked
by an elevated line near their bases.

It cannot be mistaken for the conica, nob., for in that species
the aperture is obviously oblique.

Melania proxima. — Shell conic, rather slender, black, gradu-
ally attenuated to the truncated apex ; suture moderately impressed ;
aperture longitudinal, within milk white ; labrum with the edge
not undulated, or but very slightly, and obtusely so near the supe-
rior termination.

Length to the truncated apex, nearly three-fifths ; greatest
breadth less than one-fourth of an inch.

Professor Vanuxem obtained this species in a small brook
which discharges into the Catawba river, near Landsford, Chester
district. South Carolina, and also in the Warm Springs, Buncombe
county, North Carolina, and in the French Broad river, of the

116

same county. It resembles the preceding very closely, but is de-
cidedly more slender, and like that shell it has two elevated lines
on the inferior margin of terminal whorls. The interior of the
aperture in many specimens is of a dull reddish color, and in some
the same part exhibits the appearance of two or three obsolete
bands. Another variety, which Mr. Yanuxem obtained from a
limestone spring near Broad river, Spartanburg district. South
Carolina, is of a pale horn color. In a stream of the Saluda range
of mountains near Mill Gap, in Rutherford county, he found
another variety of a somewhat smaller size, tinged with reddish-
brown, and generally distinctly banded within the aperture ; one
of these specimens is very remarkably truncated, presenting only
about one whorl and a quarter. The same variety also inhabits a
brook near the Table rock. A variety which seems to differ from
the latter only in size, was found by Mr. Vanuxem near Douthard's
Grap, of the Saluda mountains; the largest specimen he sent from
that locality is only about three-tenths of an inch long.

Melania subglobosa. — Shell subglobose, brownish horn
color ; spire but little elevated, not half the length of the aperture ;
volutions about four ; aperture rounded, nearly as broad as long ;
within more or less tinged with dull red; labium a little flattened.

Length three-fifths of an inch, greatest breadth eleven-twentieths
of an inch.

Professor Vanuxem found this curious shell in the north fork of
the Holstein river, Virginia, where they are extremely abundant.
In the old shells the surface, and particularly that of the spire, is
considerably corroded, presenting the appearance of having re-
ceived a fortuitous deposition of calcareous matter. This corrosion,
however, does not extend to the destruction of any of the whorls,
as is the case with many shells, but its effects seem to be confined
to the exterior. It is a second species of my proposed genus An-

OULOTUS.

All the striae of the operculum are concentric to the superior
angle.

PiRENA SCALARIFORMIS. — Shell turrctcd, gradually tapering to
the apex, which is acute; whorls rounded, crossed by numerous
elevated, regular lines, which, on the body whorl, are terminated
near the base by five or six more cr less profound revolving grooves;
.suture pretty deeply impressed, with generally one of the

117

grooves above it, so as to appear double ; color pale, with several
revolving reddish-brown lines ; aperture rounded : labrum thick-
ened, somewhat recurved; a slight but very obvious sinus at base,
and another very slight, more obtuse one near the junction with
the preceding whorl ; umbilicus none.

Length nine-tenths of an inch.

Mr. Titian Peale found this handsome and curious shell in
great abundance in the fresh water lakes of the Florida Keys. It
is most certainly a fresh water shell, yet it is destitute of an epi-
dermis. The labrum thickens with age ; the operculum is orbicu-
lar, and so small as to admit of the animal retiring one half the
length of the shell. It differs from Ilelama, 3Ielanopsis, and
Pirena, in the rotundity of the aperture, the thickened labrum,
and comparative smallness of the operculum.

The tenfacula of the animal are two in number, and the eyes are
placed a little above their exterior base.

[J. A. N. S., vol. V. p. 129, et seqq. Nov., 1825.]

Fusus FLUViALis. — Shell fusiform, olive-green or brownish ;
spire much elevated, gradually tapering; volutions nearly six,
wrinkled across, and with a series of elevated undulations on the mid-
dle ; suture consisting only of an impressed line ; aperture somewhat
fusiform ; within whitish, more or less with dull reddish, and with
several lines of that color, sometimes confluent ; labrum on the
inner margin immaculate, edge undulated ; canal rounded at tip ;
columella very concave.

Length one and eight-tenth inches ; aperture nineteen-twentieths
of an inch ; greatest breadth nineteen-twentieths of an inch.

Professor Vanuxem found this curious and highly interesting
shell on the north fork of the Holstein River, near the confluence
of a brook of salt water. From the name of the genus it might
reasonably be supposed to be a marine shell, but it has never been
discovered on the coast, and seems to be limited to a very small
district of the Holstein River, in company with Unio cariosus, sul-
tentus, nobis, Melania subglohosa, nobis, and no doubt other flu-
viatile shells. When the inhabitant becomes known it may autho-
rize the formation of a new genus, but there appear no characters
in the formation of the shell that would really distinguish it from
Fusus.

118

Unio subtentus.— Oblong-oval, subcompressed, slightly con-
tracted at the middle of the base, dull yellowish brown ; beaks not
prominent, decorticated ; dorsal edge regularly arcuated, without
any appearance of an angle ; anterior margin with numerous slightly
reflected ribs.

Breadth three and one-fifth inches; length more than one and
a half inches.

This species was found by Professar Vanuxem in the north fork
of the Holstein River, in company with U. cariosus, nobis, Melania
suhglobosa, nobis, and Fusus fluvialis, nobis.

In consequence of the ribbed appearance of the anterior margin
of the shell, it has much similarity to an Alasmodon, but the
lamelliform teeth are prominent and distinct.

Alasmodonta ambigua. — Shell transversely oblong-oval ;
somewhat inflated, rather thin, dusky, wrinkled ; anterior and
posterior margins almost equally rounded ; hinge margin parallel
with the base ; basal margin a little compressed in the middle ;
beaks not prominent, approximate, their surface slightly undulated ;
a very obtuse, hardly elevated undulation extends from the
beaks to the junction of the basal and anterior margins ; hinge
with very small, obsolete primary teeth; within somewhat iri-
descent ; posterior and basal portion milk-white ; hinge cavity
brownish.

Breadth one and four-fifth inches ; length four-fifths nearly.
This is one of the many fine shells which I obtained in the
North-western territory, when travelling with Major Long's party.
It forms a link between the genera Alasmodonta and Anodonta.
When young the primary teeth are obvious, but when the shell
arrives at the full growth the teeth are obsolete, and in some in-
stances, not at all visible.

[J. A. N. S. vol. V. p. 207, et seqq., Feb, 182G.]

Delphinula ? LAXA. — Whorls all separate.

Inhabits the coast of South Carolina.

Shell subovate, nearly glabrous, whitish, slightly tinged with
dull yellowish ; whorls rounded, perfectly disjoined throughout,
rapidly attenuated to the apex ; a dilated, rugous, shallow groove
on the line of the umbilicus ; aperture oval-orbicular, with an acute
edge.

119

Greatest breadth about nine-tentlis of an iocli.

This very remarkable shell was sent to me for examination by
Mr. Elliott; who has found but a single specimen ; it must there-
fore be considered very rare.

On a first view I was inclined to refer it to the genus Vermetus,
in consequence of the separated nature of its volutions, and the
broken apex of the spire, but a more careful examination exhibited
the broad rugous groove, analogous to that in the umbilicus of
many shells, and seemed to show its more close alliance with the
present genus.

Can this be a monstrosity of a Natica, as the Oornu of Born is
said to be a malformation of Helix aspersa, Mull. ?

TuRRiTELLA CONCAVA. — Shell subulate, white ; volutions more
than ten, concave in the middle, and sculptured with from two to
four obsolete, impressed revolving lines, and with an apicial and
and basal band of about fifteen longitudinal undulations on each
volution ; the basal band passes round the middle of the body
whorl ; suture very slightly impressed, interrupting the continuity
of the undulations in the adjacent bands; canal rather prominent.

Length eleven-twentieths of an inch ; greatest breadth less than
one-quarter of the length.

For this species I am indebted to Mr. Stephen Elliott, of
Charleston.

TuRRiTELLA iEQUALis. — Shell subulate, white ; volutions ten,
each with about twenty-two transverse, elevated, obtuse, equal
lines, with interstitial grooves of the same diameter; suture dis-
tinct, impressed ; aperture rounded at base, and destitute of any
distinct emargination.

Length one-fifth of an inch.

ScALARiA MULTiSTRiATA. — Shell tapering to an acute apex ;
white ; whorls eight ; costa regular, equidistant, moderately ele-
vated ; altogether wanting on the three terminal whorls ; inter-
stitial spaces with very numerous, approximate, impressed lines ;
aperture oval.

Length about one-half of an inch. Inhabits the Southern
coast.

I obtained two specimens of this shell on the coast of East
Florida, and I am indebted to Mr. Stephen EUiottt for a much

120

better specimen than either of them, from the coast of South Caro-
lina. It is readily distinguished from the two other species which
inhabit our shores, the dathrus of authors, and the lineata, nobis,
by the numerous small indented^ lines that occur in the spaces be-
tween the costoo, and at right angles with them.

Infundibultjm depressum. — Shell depressed, fragile, with
small concentric irregular wrinkles ; volutions three ; suture not
profoundly indented : apex not central ; base oval, almost orbicu-
lar ; umbilicus oblong ; internal plate small.

Greatest diameter of the base rather more than one-fifth of an
inch.

This highly interesting shell was found by Mr. Stephen Elliott,
on the coast of South Carolina. Amongst a number of curious
shells, natives of New Holland, Timor, and the Isle of France, pre-
sented to the Academy by Mr. Lesueur, a species of this genus
occurs, which is somewhat similar to ours, but it is much larger ;
its greatest basal diameter being three-fourths of an inch in length,
its suture is more profoundly indented, and its surface wrinkled
with much regularity.

Natica triseriata. — Shell longitudinally suboval, approach-
ing subglobular ; volutions five ; body whorl with three revolving
series of large oblique, parallel, oblong-quadrate, dark reddish-
brown or blackish spots, about twelve in each series ; umbilicus
rounded, not contracted by the callus ; suture not impreseed ; spire
with but one series of spots on each volution.

Length two-thirds ; width eleven-twentieths of an inch. In-
habits the Northern coast. Boston harbor.

This shell may be compared to the JST. intrvcata of Donovan,
which is comprehended by Dillwyn amongst the varieties of N.
canrena. It certainly appears to be closely allied to that very
common species of the British coast in its configuration, excepting
that it is perhaps somewhat more elongated, and that the shoulders
of the whorls are much less convex, and the suture, consequently,
less deeply impressed. In a very perfect specimen presented to
the Academy by the Vice-President, Mr. Zaccheus Collins, the
two lower series of spots are jointly included by a pale yellowish-
brown band ; beneath this band the base of the shell is pure
white ) the shell is also white above this band, excepting that the
spots of the superior series are connected by a pale yellowish-brown

121

color. This species like the canrena, seems subject to many-
varieties. Oa two apecimens, for which I am indebted to Mr.
Stone, the pale yellowish-brown color is covered by a cinereous
tinge, and on one of them two lower series of spots towards the
labrum are confluent at their inner extremities into one series ; in
another specimen the spots of each series are so confluent with
each other on the back of the shell and towards the^ labrum as to
represent three continuous bands.

I have not yet found this species so far South as Great Egg
Harbor.

From the examination of some specimens of JSfaticse from the
same coast, presented by Mr. Collins, I am inclined to think that
this species grows to a considerable size, and attains the length of
two and three-fifths inches, that it then loses its spotted bands, but
always retains the whiteness about the umbilicus, and this latter
part as well as the callus, and indeed the whole outline of the shell,
remains unaltered.

VoEVARiA OANALICULATA. — Shell whitish, immaculate, cylin-
dric, with very minute obsolete wrinkles ; spire convex, very little
elevated, mammillated at tip ; volutions about five, with their
shoulder very obtusely grooved ; labrum with the edge arcuated ;
labium overspread with a calcareous lamina, and with a single
oblique fold or small tooth near the base.

Length from three-twentieths to nearly one-fifth of an inch.

I received specimens of this singular shell from Mr. Elliott, of

South Carolina, who obtained it on the coast of that State. The

arcuated form of the edge of the labrum is only perceived when

the part is viewed in profile.
t
Nassa unicincta. — Shell yellowish-white or cinereous, subo-

vate-conical ; whorls with numerous revolving lines and transverse
undulations, the former about eleven or twelve in number, with
often a smaller obsolete one in the intervening spaces ; undula-
tions about ten to the body whorl, placed at the distance of the
length of their own diameter apart, and somewhat closer on the
spire ; whorls eight ; apex acute ; body whorl with a brown band,
sometimes obsolete, interrupted by the undulations, and consisting
of about two spots in each of the intervening spaces ; labrum
■within with ten parallel striag, which revolve on the inner surface

11

122

of the shell ; labium in the middle concave, with about two obso-
lete stria3, and a more profound one at base.

Length seventeen-twentieths ; breadth nearly nine-twentieths of
an inch.

In the collection of the Academy is a shell from the West
Indies, to which our species is very closely allied ; and although
the striae of the labrum are double in the former, yet it is probable
that the two shells will be found to constitute one species, when
more specimens are examined and carefully compared. In the
systems it will probably arrange near to iVi vnlgotum.

For this shell I am indebted to Mr. Stephen Elliott, of Charles-
ton.

Nassa alba. — Shell ovate, white, immaculate, longitudinally
ribbed or undulated, and with spiral striae ; ribs equal, equidistant,
symmetrical, from ten to eighteen on the body whorl ; strise equal,
equidistant, filiform, elevated as distinctly upon the ribs as in their
interstices, and from seventeen to twenty in number on the body
whorl ; whorls seven, convex ; suture deeply indented ; aperture
suborbicular ; labrum with a larger rib than the others on the ex-
terior, and striate within ; labium, plate distinct, entire, but not
expanded, with an indented line near the base, and a prominent one
near the junction with the labrum.

Length nine-twentieths ; breadth three-tenths of an inch.

Inhabits the southern coast of East Florida, and the West India
Islands.

I owe this beautifully sculptured shell to the politeness of Mr.
Elliott. It seems to be more closely allied to N. macula of
authors than to any other wiih which I am acquainted. It is,
however, distinguished as a species by its more venVicose form, by
its ribs being more rectilinear, and by the spiral striae being more
prominent and distinct. Those found on the coast of Florida are
in no respect different from specimens brought from the West
India Islands.

Nassa lunata. — Shell reddish-brown, with about six volu-
tions ; whorls with two revolving lines of dilated, sublunate, whitish
spots, and sometimes a third one at base ; suture not deeply im-
pressed ; labrum dentate on the inner submargin, the superior teeth
more prominent ; labium with the plate not thickened.

123

Yar. Of. Shell white, with two revolving reddish-brown dilated
lines.

Length three-twentieths of an inch. Inhabits the coast of
the Southern States. Cabinet of the Academy and Philadelphia
Museum.

Animal pale, whitish ; foot linear, nearly as long as the shell,
acute behind, hardly larger than the respiratory trunk, truncate
before ; trunk more than half as long as the shell, obtuse at tip,
with a brown undulation near the tip, and another near the base ;
tentacula short, cylindrical, annulate with blackish on the middle ;
eyes black, placed on the base of the tentacula.

Found adhering under stones, fuci, &c., in the bays ; numerous.
It varies in color and in markings ; the white sometimes predomi-
nates, and reduces the reddish-brown to one or two linear, trans-
verse, undulated lines. A variety occurs on the coast of Maryland,
which is white, with two or three reddish-brown, irregular-revolv-
ing lines.

FusTJS 10-coSTATUS. — Shell somewhat ventricose, very short,
fusiform ; the beak being much shorter than the spire ; with six
or seven volutions, which are each obliquely flattened above the
shoulder, and spirally ribbed ; these costce are elevated, semicylin-
dric, and, with the exception of the two superior ones, equidistant •
sutural costge remote from that of the shoulder ; interstitial spaces
with small lines parallel to the costse ; the latter are ten in number
on the body whorl, three on the second whorl, three on the third,
and obsolete on the fourth.

Length three and three-tenths inches. Greatest width one and
nine-tenth inches. Length of the spire one and two-fifth inches.

This interesting species was presented to me by Mr. Zaceheus
Collins, who obtained it from the coast near Boston. The summit
of the spire, of two specimens before me, is partially removed, ex-
hibiting in the interior a close arrangement of very numerous
septse, formed by the animal at different times, as it increased in
size, and gradually abandoned the apex. It approaches veiy closely
in character to the genus Buccinum.

Fusus BICOLOR. — Shell short, fusiform ; the beak subequal to
the length of the spire ; volutions five, convex, with abrupt, promi-
nent, regular, equidistant undulations, which, on the body whorl,

124

are thirteen or fourteen in number, extending from the suture
about half the distance to the tip of the beak, and near the suture
exhibiting a tendency to rise into arched scales ; the whole surface
of this shell is sculptured with small revolving grooves, to the num-
ber of from twenty-five to thirty on the body whorl ; inferior
moiety of the body whorl tinged with rufous ; suture profoundly
impressed ; aperture gradually diminishing to the beak ; striae of
the labrum within distinct, sometimes obsolete or wanting.

Length nine-twentieths ; greatest breadth more than one-fourth
of an inch. Inhabits the Southern coast of East Florida.

The aperture is not suddenly contracted at the origin of the
beak channel, as in many species, but is gradually diminished in
width, much like Montfort's Q.(^u.xe of Lafirm /ihsus.

For this shell I am indebted to Mr. Elliott.

Patella alternata. — Shell conical, with upwards of thirty
obsolete, hardly raised, unequal ribs ; apex obliquely curved, the
tip pointing nearly in a parallel direction with the surface of the
shell, and acute ; color brown, radiated with white ; base oval.

Basal length three-tenths of an inch. Inhabits the Southern
coast of East Florida.

Communicated by Mr. Elliott. It seems to approach the leti^o-
pleura, as described by authors, excepting that the base is not
ovate, as the base of that shell is said to be.

Calyptr^a striata. — Shell oval, prominently convex, with
numerous, slightly elevated, equal, equidistant radiating lines ;
summit glabrous, wax-yellow, subacute, inclining towards the left
side and the posterior end ; inner valve patelliform, dilated, attached
by one side to the shorter side of the shell ; acutely angulated at
the anterior line of junction, and rounded behind, and rapidly at-
tenuated to an acute tip, which nearly corresponds with the inner
apex of the shell.

Length less than nine-tenths of an inch.

This species belongs to my indicated genus Dispotxa. I am
indebted for it to Mr. John S. Phillips, who obtained two speci-
mens on the coast of New Jersey, about three miles north of Long
Branch.

Venericardia tridentata. — Shell suborbicular, subequi-
lateral, thick and ponderous, with about eighteen convex, longitu-

125

(iinal ribs, canccllate by concentric, elevated lines, which do not
penetrate into the interstititial narrow spaces, and which are obsolete
on the umbo, and on the anterior side ; inner margin deeply cre-
nate ; hinge with two diverging teeth, separated by a large cavity
on one valve, and on the other a single large, triangular, promi-
nent, recurved tooth, closing into the cavity.

Length one-fourth of an inch, breadth rather more.

This curious shell was discovered by Mr. Stephen Elliott, on the
coast of South Carolina. Its characters do not at all correspond
with those of Venericardia, as defined by Lamarck in his last
work, the Animaux sans Vertebres, where he attributes to the genus
" two oblique, cardinal teeth directed to the same side." In the
Ann. du Mus., vol. 7, page 55, he admits, however, that "■ in cer-
tain species, which ought, perhaps, to be separated from the Veneri-
cardes, there is on one valve but a single cardinal tooth, and upon
the opposite valve two divergent cardinal teeth." These charac-
ters, I conceive, correspond with the shell above described ; and
although, should they be tolerated, an artificial assemblage will be
the result, yet, for the present, I refer this shell to the genus Veneri-
cardia, under this authority of Lamarck.

This species will be regarded as an interesting addition to the
Fauna of the present world. The first recent species was described
by Lamarck as a native of New Holland. All other known species
are found only in the fossil state.

Tellina intastriata. — Shell subovate, angulated at the an-
terior base, transversely wrinkled, and within slightly striated lon-
gitudinally. ,

Coast of East Florida.

Shell white, immaculate, ventricose ; wrinkles distinct, and with
obsolete, longitudinal striae ; posterior slope near the hinge parallel
to the base ; posterior end obtusely rounded ; anterior hinge slope
rectilinear, oblique ; anterior end rounded ; fold rather profound,
extending from the beak to the junction of the base, with the an-
terior end } base viewed from the disk of the right valve subrec-
tilinear, but very much arcuated with the concavity of the shell ;
hinge teeth small, lateral teeth none ; within longitudinally obso-
letely striated ; beak rather before the central.

Length one and three-fifths inch, nearly 5 breadth two and one-
tenth inches, nearly.

126

This shell was handed me for examination by Professor Green,
in whose cabinet the specimen is preserved; a right valve is in the
collection of Mr. Hyde ; in general outline it resembles fig. 3, pi.
287, of Encyel. Meth.

Tellina lateralis. — Shell transversely subovate ; beak nearly
central ; posterior margin regularly rounded ; anterior margin ros-
trated, the rostrum turned to the left, and slightly gaping ; ligar
ment slope rectilinear ; basal margin regularly ai'cuated, a little
contracted near the rostrum; valves whitish, often tinged with
ferruginous, with small concentric wrinkles and slight waves ;
within white, a little sculptured with the external waves ; lateral
teeth none ; cardinal teeth two on one valve, and one with another
hardly elevated filiform one on the other.

Inhabits the coast of the United States. Length one and eleven-
twentieths inch ; width two and three-twentieths inches.

This species is more commonly found upon the Southern coast,
where it is abundant, but perfect specimens are very rare.

Tellina decora. — Shell transversely subovate, rosaceous, or
white, with rosaceous radii ; not much compressed ; numerous,
minute, concentric wrinkles, and regular, oblique, equidistant lines
crossing them ; anterior margin destitute of the oblique lines ;
posterior lateral tooth of the left valve prominent, the others obso-
lete ; apex a little before the middle.

Length more than one-half of an inch ; breadth seventeen-twen-
tieths of an inch.

The largest specimen, brought by Mr. T. Peale from the Southern
coast of East Florida, is one inch in breadth.

In the character of the oblique striae this species is allied to 1\
Iris, nobis, but it is amply distinguished by its much greater size,
less compressed form, oblique stritc, by its color, &e.

PsAMMOBiA PUSCA. — Shell compressed, transversely subovate,
thin and fragile ; wrinkled concentrically, and covered with a fus-
cous or yellowish-brown epidermis ; apex not prominent, central ;
anterior margin more narrowed than the posterior one, with a slight
and obtuse wave passing along the anterior submargin ; posterior
margin very obtusely rounded ; within white ; teeth diverging re-
motely, very slender, filiform, and hardly elevated.

Var. a. Epidermis whitish, slightly tinged with yellowish.

127

Length one and one-twentieth inches ; breadth one and seven-
twentieths inches. Inhabits the estuaries of Georgia. Cabinet of
the Academy and Philadelphia Museum.

Several specimens of dead shells were brought up from the
bottom of the Sound, near Jeykill island, by the fluke of our
anchor.

Amphidesma radiata. — Shell transversely oval, orbicular, a
little compressed ; apex nearly central, a little prominent ; posterior
slope somewhat concave near the beak ; anterior slope rectilinear
to the middle ; disk somewhat regularly wrinkled transversely, and
with minute longitudinal striae, white, with more or less rosaceous
radii, which are sometimes obsolete ; anterior submargin, with a
slight veiy obtuse undulation ; cardinal teeth two in each valve,
elevated, slender, unequal ; lateral teeth very distinct ; the 'poste-
rior one nearer the primaiy teeth, and shorter than the anterior
one ; interior ligament cavity profound, fusiform, nearly parallel
to the anterior slope ; within tinged with yellow, and the rosaceous
radii are distinct.

Length nine-tenths inch ; breadth rather more than one inch.

Many specimens of this pretty species were brought from the
Southern shores of East Florida, by Mr. Titian Peale, and I ob-
tained a worn individual a few years since, on the coast of Gleorgia,
measuring one inch and two fifths in breadth.

It resembles the species I formerly described under the name of
A. oi'hiculata, but it is wider in proportion to the length, &c.

Amphidesma lepida. — Shell very much compressed, subtri-
angular, remarkably thin, pellucid, equilateral, somewhat iridescent,
with numerous concentric wrinkles, and equally numerous very
minute regular, longitudinal striae, which, on the anterior margin,
curve towards the anterior edge, and on the posterior margin curve
in the same manner towards the posterior edge ; cardinal teeth
obsolete ; lateral teeth prominent.

Length rather more than one-fourth of an inch ; breadth lesp
than one-fourth of an inch.

This shell was sent to me by Mr. Elliott, who found it on the
coast of South Carolina.

128

[No. 4, Long's Expedition, &c. vol. ii. p. 261, et seqq. 1824.]

Planorbis deplectus. — Shell dextral, depressed; whorls
nearly five, minutely and regularly wrinkled across, wider than
long, with a much depressed rotundity above, descending to an
acute lateral edge below the middle ; spire not impressed j suture
indented, but not profoundly; beneath a little concave in the
middle, exhibiting one-half of each volution to the apex ; whorls
flattened, slightly rounded ; aperture declining very much, sub-
oval, the superior portion of the labrum considerably surpas-
sing the inferior portion, and taking its origin a little above the
carina ; inferior portion of the labrum terminating on the middle
of the inferior surface of the penultimate whorl.

Greatest breadth two-fifths of an inch.

This shell was presented to me by Dr. Bigsby, who collected
many specimens in the waters of the North-west Territory.

It resembles the cxacuous, nob., but the aperture does not em-
brace so large a proportion of the preceding volution, and the
^'olutions on the inferior portions of the shell are consequently
more obvious, and the umbilicus is but slightly indented ; the
upper portion of the labrum does not extend so far beyond the
lower portion, the aperture declines much more, and the carina is
less acute. It has also an afl&nity for the carinatus of Europe,
but in addition to other differences, the aperture of that species
declines but little, if at all, and the carina is an elevated revolv-
ing line. The aperture embraces the penultimate volution about
as much as in the rotundatus of Europe, to which our shell is also
allied, but differs in its declining aperture, and the less degree of
rotundity of its whorls on their upper surface. PI. 15, fig. 8.*

Planorbis corpulentus. — Shell dextral ; whorls more than
three, rather rugged with coarse wrinkles, much higher than wide J
superior surface much flattened, and edged by an abruplr acute
line, which is distinct to the aperture ; sides hardly rounded, and
terminating below by another abrupt edge, which is not quite so
definite and acute as the superior one ; spire slightly concave ;
umbilicus exhibiting a portion of each of the rapidly retiring
whorls to the apex ; aperture longer than wide, the superior part
extending higher than the preceding volution, and the inferior

* [Plate 74 of tliia reprint.— -Ed.]

129

portion declining much lower than the inferior line of the same
volution.

Greatest breadth three-fourths of an inch. Length of the
aperture nearly half an inch. Length of the penultimate whorl
near the aperture rather more than three-tenths of an inch. In-
habits Winnepeek river, Winnepeek lake, Lake of the Woods,
and Rainy lake; common. PI. 15, fig. 9.*

Of this species I collected numerous specimens, but had the
misfortune to lose them all, as well as a great number of interest-
ing terrestrial and fluviatile shells, on our return to the settlements,
and I am indebted to the liberality of Dr. Bigsby for the indi-
vidual above described. It is closely allied to trivolvis, nobis, but
is much less rounded on the sides of the whorls, the carinae are
more prominent, the upper side is much more horizontally flattened,
the labrum is less rounded, and the whole shell is larger and
higher in proportion to its width, and the aperture extends both
above and below the penultimate whorl.

Planorbis campanulatus, nob. Falls of Niagara.

Planorbis trivolvis, nob. North-west Territory and Falls of
Niagara.

Planorbis parvus, nob., is common in the waters of the North-
west Territory, and may be found in plenty crawling upon the rocks
near the shores. They vary in size from those found in the Eastern
States, being less than half as large.

Planorbis armigerus, nob. St. Peter and Red rivers, com-
mon.

Planorbis bicarinatus, nob. North-west Territory, rather
common.

Lymneus megasomus. — Large, dilated suboval; spire short,
rapidly diminishing, acute ; whorls about five, rounded, obtusely
wrinkled across ; body-whorl large, the wrinkles very obvious ;
suture deeply impressed ; aperture subovate, much longer than the
spire, within chesnut-brown ; collumella white.

Length more than one and six-tenths of an inch. Length of
the aperture more than one inch. Greatest diameter one inch.

This remarkably large and fine species was found in Bois Blanc
Lake, North-west Territory, by Dr. Bigsby, to whom I am indebted
for specimens. The color is brownish, sometimes lineated across

* [Plate 74 of tMs reprint.— Ed.] •

130

the body whorl with dull greenish and pale oehraceous ; and the
chesnut-brown color of the interior of the shell, combined with its
large dimensions, distinguish this species from all others yet die-
covered in this country. PI. 15, fig. 10.*

Lymneus emarginatus, nob., from Lake Namakan, north of
Lake Superior ; collected by Dr. Bigsby.

Lymneus elongatus, nob. Rainy Lake and Seine river, Dr.
Bigsby.

Lymneus desidiosus, nob. Falls of Niagara.

Physa heterostropha, nob. North-west Territory.

Valvata sincera. — Shell subglobose-conic ; whorls nearly
four, accurately rounded, finely and regularly wrinkled across ;
aperture not interrupted by the penultimate whorl nor appressed
to it, but merely in contact with it, the labrum not diminished in
thickness at the point of contact ; umbilicus large, exhibiting the
volutions.

Breadth less than one-fifth of an inch. Inhabits North-west
Territory.

For this species I am indebted to Dr. Bigsby. It is very similar
to the tricarinata, nobis, but is destitute of carinated lines, and
the umbilicus is rather larger ; it differs from the ohtusa of
Europe, also, in the much greater magnitude of the umbilicus.
PL 15, fig. 11.*

Paludina limosa, nob. North-west Territory.

Ampularia depressa. — Shell ventricose, subglobular, obso-
letely banded with obscure green ; whorls four, slightly wrinkled ;
body whorl more prominent above, somewhat flattened towards the
suture, of a pale olivaceous color, which is almost concealed by
numerous, unequal, longitudinal and transverse greenish and brown-
ish lines ; spire very much depressed ; aperture suboval, within
somewhat glaucous, on the margin exhibiting the bands distinctly ;
labrum simple, as much rounded above as below ; umbilicus small,
nearly closed.

Greatest width one inch and nine-twentieths. Total length one
inch and a half Length of the aperture one and one fifth of an
inch nearly. Inhabits East Florida.

During an excursion to East Florida, in company with Messrs.
Maclure, Ord and T. Peale, I obtained a single dead and imperfect

* [Plat« 74 of thiB reprint. — Ed.]

131

specimen of this interesting shell. It occurred in a small creek,
tributary to St. John's river, and on the plantation of Mr. Fatio.
Captain Le Conte of the Topographical Engineers, has since pre-
sented me with a perfect specimen, with the information that he
observed them in very great numbers on the shores of Lake
George, a dilatation of St. John's river ; that in some places the
dead shells were piled up confusedly to a considerable height, and
that the Numenius longirostra feeds upon the living animal. The
spire is still less elevated than that of the glohosa of Swainson.
PI. 14, fig. 2.*

Melania virginica, nob. Falls of Niagara.

Anodonta gibbosa. — Shell thin and very fragile ; much in-
flated ; anterior and hinge-margins compressed, the former alated ;
surface pale yellowish testaceous, finely radiate with green, and
having somewhat regular concentric minute undulations ) within
somewhat iridescent.

Length about one and nine-tenths, breadth two and nine-tenths
of an inch.

This shell exhibits a remarkable appearance, in the unusually
great convexity of the disks and umbones. It is strikingly dis-
tinct, and was presented to me by Captain Le Conte of the Topo-
graphical Engineers, who informs me that it is an inhabitant of
South Carolina. PI. 14, fig. 3, 4.*

[No. 5. New Harmony Disseminator.]

[The greater portion of the descriptions published in this work were in-
cluded in Mrs. Say's "Descriptions," ^c. These are copied from her re-
print ; the original date and page of each species is not given here, but may
readily be found in the Index. Those descriptions which Mrs. Say did not
reprint, on account of their having been repeated by Mr. Say in the " Ameri-
can Conchology," will be found under that head. This arrangement was
necessary to prevent the necessity of transcribing the descriptions to MSS.
The species thus omitted by me are specified in the following list, — Ed.]
For the following species see American Conchology.

Unio dehiscens, Unio peksonatus,

" ridibundps, " apiculatus,

Alasmodonta confbagosa.

Unio cicatricosus. — Shell transversely subovate: posterior
margin very short, hardly extending beyond the beaks, regularly

* [Plate 73 of this reprint.— Ed. ]

132

rounded : anterior margin rounded, or veiy obtusely angulated :
umbo elevated : fosset behind tbe beaks, moderate, wider tban
long, not angulated behind : disk deeply wrinkled or undulated
with a series of transverse elevations, sometimes separated by small
longitudinal lines, so as to resemble, as it were, drops of a liquid,
extending from the umbo to the base : within white : teeth direct. "

Length, about two inches and nine-tenths; breadth, three
inches and seven-tenths. Convexity, nearly two inches. Inhabits
Wabash.

A common species, distinguishable by the single series of trans-
verse elevations on the middle. The allied species are U. cardice
and mcurvis, nob.*; but besides other characters, it may be dis-
tinguished from either by the less prominent nates, the smaller
fosset, and the series of the disc. Amongst the numerous species
sent to me by Mr. Barnes, previously to the publication of his
paper, was a small valve of this species, but it was then referred
as a variety to the convenient but obsolete receptacle of this
genus, U. cr-assus.

Unio velum. — Transversely elongate suboval, compressed, very
fragile and thin, olivaceous, radiated with green ; umbo not
prominent, placed far backward ; base subrectilinear ; anterior mar-
gin more widely rounded in the posterior margin, with prominent
membrane, erenate at its tip ; within margined with opake white ;
primary teeth, a conic one in the left valve, with a recipient sinus
in the right valve ; lateral teeth simple and single in each valve.

Length, more than half an inch ; breadth, less than one inch and
one-fifth. Inhabits the Kentucky River.

This pretty species is remarkable in having the epidermis ex-
tended into a broad, erenate membrane, terminating the anterior
margin. In the form of the teeth and the white interior margin
this shell resembles the U. monodonta ; and, in fact, I was led
from these characters to suppose it the young of that shell, but
afterwards finding the young, and perceiving that the umbo was

* I think these two species have long since been published under the
names of corduta and intorta. I therefore suppress the descriptions here.
I may remark, further, that the descriptions of Unio here given were
chiefly made about three years since, together with nearly twenty others,
which I suppressed, as the species were either anticipated or subse-
quently made known in the works of recent naturalists.

133

iOt so far backward as in the present shell, and the remarkable
iiembrane, induced me to describe it as new. It occurred on the
ocky shore of the river, and appears to be rare.

Unio purpuriatus. — Transversely oval, slightly oblong, in
ome specimens with a little tendency towards ovate ; dirty yellow-
sh or fuscous, obscurely radiate with blackish-green : beaks,
tehiud the middle, hardly raised : anterior edge rounded, or rather
lomposed of two nearly rectilinear lines : posterior margin rounded:
linge margin regularly rounded : cavity of the hinge membranes
behind the beaks) narrow, but very obvious : basal margin arquated,
I little compressed in the middle, and sometimes almost contracted
n that part : within, purple ; margin livid ; anterior submargin
ridescent : primary teeth nearly direct, rather thick, striated •
ateral teeth hardly extending beyond the sinus of the hinge
margin.

Length, one inch and three-fifths ; breadth, three inches and
)ne-tenth. Convexity, over nine-tenths of an inch. Var. a.
Within white : Var. b. Within dull yellowish. Inhabits Mexico.

For this species I am indebted to Mr. Maclure. It was found
by William Bennet in a stream a few leagues from Vera Cruz,
where it is abundant. It resembles U. purpureus, nob., but dif-
fers in having the teeth more direct; in the lateral teeth being
shorter, with respect to the sinus of the hinge margin ; in having
the greatest breadth at the middle of the anterior margin, &c.

In the young and middle-aged specimens the radii are very
distinct, but are obsolete in old specimens. The umbones are
widely decorticated in age, but seldom are they so deeply eroded
as to disclose the waxen colored Stratum.

It may be considered as the ]\Iexiean analogue of the p«r-
imreus.

Unio metallicus. — Transversely ovate, veiy slightly oblong :
dull yellowish, tinged with coppeiy, particularly on the umbones :
beaks slightly elevated, not decorticated, undulated ; the undula-
tions obsolete in their middles, and not extending on the umbo
placed far back : hinge margin prominently arquated : posterior
margin very short, rounded : anterior margin rounded : basal mar-
gin subrectilinear : within liver color : iridescent on the anterior
margin : cardinal teeth rather long, somewhat tuberculous, not
very prominent ; that of the right valve not abruptly terminated

134

before, but gradually diminishing (as that of some Alasniodontas ;)
lateral teeth rather slender.

Length (at the anterior tip of the lateral teeth) one inch and
one-fifth ; breadth, nearly two inches and one-fifth. Convexity,
four-fifths of an inch. Inhabits Mexico.

This shell is remarkable for the coppery tint, which is more
obvious on the umbones. It was obtained in Lake Chalco ? and
was presented to me by Mr. Maclure. In the young state it is
radiate with green before, and the adult has a very thick granular
deposite of carbonate of lime on the anterior half of the shell,
which is in the water and above the mud. The species appears to
be abundant.

Unio subrostkatus. — Transversely elongated, subrostrated,
radiated.

Inhabits Wabash.

Transversely elongate subovate, brownish or pale ochreous, with
numerous dark green radii : beaks but little elevated with a few,
small angular, concentric lines : ligament margin a little compress-
ed : anterior margin somewhat elongated, hardly subrostrated :
separated by an obtuse angle from the ligament margin : base
arquated : posterior margin rounded : within white, often slightly
tinted with flesh color; somewhat iridescent on the margins,
particularly the anterior margin : substance of the shell not thick :
teeth very oblique, crested.

Length, one inch and two-fifths ; breadth, three inches and one-
fifth. Convexity, hardly over one inch.

This may be said to be the analogue of the U. nasutus, nob.,
of the Western waters. The rostrum, however, is not so definite,
and it is a more convex shell. The aged shell is dark brown, but
near the beaks reddish brown.

Note. — A short time since, I began a review of the American species
of Unio hitherto described by naturalists, in which it appeared to me
that much yet remains to be done, notwithstanding the laudable attempts
that have already been made to rectify the synonyma : but on advancing
somewhat in the undertaking, I found myself so much at a loss for
books and other means of reference in my insulated residence, that I
was compelled for the present to relinquish it. Tlie following notice,
however, I have concluded to publish, because it relates to the most
common species in our eastern waters.

135

Unio purpureus, nob. — The propriety of retaining this name
has recently been much questioned by two of our conchologists,
but as I do not think that, as yet, its stability is in any degree
problematical, I shall endeavor to show on what my opinion is
founded. Prof. Green remarks, " I have no doubt that the spe-
cies known commonly by the name of Uhio jnirpureiis, is the same
with the Mytilus JiuviatiUs figured by Lister, t. 157, fig. 22, and
described by Dillwyn, from Gmelin, under that name. I have,
therefore, been obliged by the rules of nomenclature, now so strictly
observed in Natural History, to restore the original specific name
of Gmelin to this interesting shell, so well known by the name of
purpureus." (Contrib. of the Macl. Lye. Vol 1. No. 2.)

I cannot discover any specific similarity of the purpureus to this
very doubtful figure, except that Lister describes it as " suhruber
ex interna parte ;" certainly the shape of the figure is more like
the cariosus or ovatus, nob., than \h.Q purpureus, and this assimila-
tion is rendered more like, when we take into consideration the
depressed anterior margin of the shell that appears associated with
it on the same page, the PotamopMla suhviridis, Gmel. But it is
all mere conjecture, for even the genus of the figure cannot now
be determined, though it is probably an AnodoDita, and as the
description of the fiuviatilis was made out by Gmelin entirely from
that figure, I should consider it as worthless, as such a latitude in
describing is reprehensible.

It is nevertheless evident that, from the situation Dillwyn
assigns to the fiuviatilis, he considered it an Anodonta, for, ac-
cording to my MSS. notes, wherein the subject of the iVayacZes was
at first discussed, he places fiuviatilis next to cygneus, and it is
followed hy stagnalis and anatinus and fucatus, all Anodontas.
Hence, if all this be correct, the rectus, triangularis or sesopus are
more nearly related to purpureus than the fiuviatilis can be ; if in-
deed, such a species as the latter exists in nature.

Mr. Lea observes, " Dillwyn describes this shell, under the name
of 3fya complanata, and refers to this figure." (Lister, 1. 150, f. 5.)
'' Dr. Green supposed this shell, so well known to all our concholo-
gists under Mr. Say's name purpureus, to be the Mytilus fiuviatilis,
described by Dillwyn from Gmelin, and referred to Lister, t. 157,
f. 12. I difier, however, in this opinion : 1. Because it is not
described as being toothed. 2. Gmelin says, " habitat in Europae

136

aquis dulcibus.' 3. The complanata answering, in description,
better to our shell, and being the first figured and described. It
appears somewhat singular to me, that the observant and able
zoologist, ]Mr. Say, had not been struck with the similitude of our
shell to Lister's figure and description. There is no species more
common in all our fresh waters, east of the Alleghany Mountains,
than this ; and nothing could be more likely than that it should be
among the first to be taken to Europe by the early voyagers to
America. In accordance, therefore, with the rules of nomencla-
ture, I have inserted the name of complanatus to the shell de-
scribed by Mr. Say under the name of purpureus." — (Trans.
Philos. Sc. Vol. 3, N. S.)

I have not, at present, the means of referring to Dillwyn's work,
and I can therefore only speak in relation to Lister's figures, 1. 150,
above mentioned, and consequently, to any description founded on
these figures. On reading the above, I was myself struck with the
singularity of the fact, that I should have overlooked the similitude,
if any, between the shell and a figure with which I was equally well
acquainted. But on a re-examination of the figure, I am in my
turn surprised that any one should have thought of bringing the
purpureus into comparison with it. How the figure can appear so
differently to different conchologists, I know not ; but certain it is
that Gmelin quoted it, with a saving mark of doubt, for Mytilus
cygneus ! ! I quoted it in the year 1819 for Unio crassus, Barnes
also quoted it for the U. crassus, and now it is supposed to repre-
sent the shell in question.

After a careful comparison of the shell with that figure, I can-
not, with any moderate concession of character, make it correspond ;
and, moreover, I cannot think that any one will be more success-
ful in this respect than I have been. But even if a strong likeness
really existed, two words of Lister's description, quoted by Mr.
Lea himself, puts the matter altogether beyond a doubt. The
words, " admodum crassus," engraved on the same plate with the
figures, admit of no misconstruction, and no approximation of the
purpureus, (which Mr. Lea says, p. 33, note, " is never ponder-
ous,") but agree very well with a variety of the unfortunate U.
crassus ; for which I originally quoted the figures, and which is
" admodum crassus." For these reasons, I tkink that cause has
not yet been shown why the name should be changed ; and, there-

137

fore, agreeably to any rules of modern nomenclature, the name
purpuretis seems fated to withstand all attacks, unless, indeed, it
can be proved, from Mr. Dillwyn's description itself, tliat be meant
this shell, when he described his contplanatus, and not that of the
figure to which he refers.

Alasmodonta sculptilis. — Shell transversely suboval, with
green radiations : umbo and summit with six or seven rather sharp
undulations, which are transverse, rectilinear, at the extremities
abruptly arquated or reflected : dorsal and anterior margin from
the summits with numerous, slender, slightly elevated lines bend-
ing in different directions.

This is evidently a young shell, but we know nothing of the
adult. The teeth are more like those of tlje undulata, nob., than
any other species, but the form and sculptured anterior margin
amply distinguish it.

It was brought from Virginia by Mr. I. Lukens, and by him
presented to me.

Alasmodonta edentula. — Shell transversely oblong-oval,
somewhat compressed, dark olivaceous or brownish, obsoletely
radiated (in the young :) nates behind the middle, but remote from
the posterior edge, but little prominent, undulated : anterior mar-
gin not remarkably compressed, and not radiated : within white,
margined with opake white more or less distinct, but sometimes
obsolete : teeth obsolete, but the peculiar curvature beneath the
beaks shows their locality.

Length, one inch and seven-tenths ; breadth, three inches. Con-
vexity, one inch. Inhabits Wabash river.

Approaches nearest to A. marginata, nob. ; but the want of
teeth, and the simple anterior margin, at once distinguish it.

Cyclas edentula. — Shell transversely oval, inaequilateral,
with somewhat elevated and regular transverse lines : beak not ele-
vated above the general surface ; cardinal tooth very small, lineolar,
oblique and not elevated higher than the edge of the hinge mar-
gin : color brown : umbones decorticated.

Length, seven-twentieths of an inch. Breadth, two-fifths of an
inch. Inhabits Canandaigua Lake.

This is distinguishable by the diminutive teeth, which are not
visible in a profile view of the hinge.

12

138

Oyclas transversa. — Transversely oblong subovate, sub-
inseqiiilateral : anterior margin decidedly more widely rounded than
the posterior margin : beak obviously elevated above the general
curvature : cardinal teeth double, distinct.

Length, over one-fourth of an inch ; breadth, nine-twentieths of
an inch. Inhabits Kentucky.

This shell is more transverse than even the simih's, nob.

Cyclas triangularius. — Transversely oval, subtriangular, sub-
equilateral : disk with transverse, rather raised lines : beak some-
what prominent; elevated much beyond the general curvature:
teeth, viewed in profile, distinct and elevated.

Length, two-fifths of an inch ; breadth, half an inch. Inhabits
Mexico.

The apex of this species is not so acutely elevated as that of
the cali/cula(a, Drap., but the shell is more drawn up to an angle
in that part.

Anodonta implicata. — Transversely oblong-oval, subcylin-
dric, yellowish olive : disk convex, the wrinkles not very promi-
nent ; urabonial slope hardly presenting a very obtuse angle or
curve : beak but little elevated, obsoletely undulated : hinge mar-
gin nearly parallel to the base, diverging a little from it anterior"
ly, and terminating in a slight, obtuse angle : within deeply con-
cave.

Length, one inch and a half; breadth, three inches and a fifth;
convexity, one inch and three-twentieths. Inhabits a pond in
Danvers, Massachusetts.

For this species, I am indebted to Dr. Harris, of Milton. It ia
more cylindrically convex than any I have met with.

As respects the proportions of length and breadth, it resembles,
A. elorif/atux, Swains. ; but the umbones are less elevated and not
placed so far back as in that species. It is also a thinner shell,
and the dorsal view is altogether different, exhibiting a regular
curvature.

Anodonta lugubris. — Transversely oblong-oval, subovate,
blackish-brown : disk convex, acutely wrinkled : umbonial slope,
with a distinct elevation or line : beak, slightly elevated, with
two or three sinnous undulations : within, white : margin, parti-
cularly before, livid : hinge margin somewhat parallel to the

139

base, at the sinus rather nearer the base than at the beak, or as
near.

Length, two and a half inches ; breadth, four inches and seven-
tenths. Convexity, one inch and four-fifths. Inhabits Cumber-
land River.

For this specimen I am indebted to Mr. Lesueur. I cannot
make it agree with the J., pi^pwracejis, Swains., though it bears
some resemblance to that species. It is, however, a more convex
shell, the beak not so far back, and much more obtusely rounded
before. The few specimens in the cabinet of my friend Lesueur
are not tinged with purle within.

It has some resemblance to Lister's fig. 9, of pi. 154, which
Dillwyn calls fucatus, but the present is a longer shell, with some-
what more elevated beaks, more rounded at the base, &c.

Anodonta grandis. — Shell very large, subovate ; disk un-
eqally wrinkled and undulated transversely, dark yellowish brown ;
umbo elevated; beak slightly elevated, with, generally, two or
three small sinuous, acute undulations ; hinge margin slightly
arquated, sometimes nearly rectilinear, somewhat angulated at its
anterior termination, thence the edge descends by a nearly recti-
linear, or slightly concave line to the anterior margin, which is
considerably narrowed ; sinus of the hinge margin, concave ; pos-
terior margin widely rounded ; within white margined, particularly
before, with dusky.

Length, nearly five inches ; breadth over seven and a half inches.
Convexity, three and a quarter inches. Inhabits Fox River of the
Wabash.

The great size of this species, distinguishes it from any other
I have met with. A favorable specimen, at first view, corresponds
with the figures on pi. 205 of the Encycl. Meth., named by La-
marck, A. trapezialis, but the diflFerent character is, in the words
of Lamarck, " La sinus de la lame cardinale est grande, et
form un angle rentrant, aigu." He described from a specimen
in his own collection, and as the figures exhibit this character,
thete can be no doubt that our shell is a distinct species.

The finest specimen I have seen was presented to me by Mr.
Oliver Evans, who obtained it in Fox River, which is a serpentine
arm of th& Wabash.

Anodonta impura. — Subovate, fragile, a little compressed.

140

dull yellowish brown ; umbo much eroded, exhibiting a chalky
white stratum, then a dull wax yellow surface ; beak a little
undulated, hardly elevated above the general curvature ; hinge
margin forming a large angle with the base, being anteriorly ele-
vated into an obtuse angle, whence the edge descends almost recti-
linearly to the anterior margin, which is equally rounded with the
posterior margin.

Length one inch and three-tenths ; breadth less than two inches.
Convexity less than seven-tenths. Inhabits Mexico.

I obtained several specimens in a ditch beside the road betwee''^
the Capitol and Tacubya. It is perfectly distinct from any
species of this countiy that I have seen. It cannot be the
A. glauca, Lam., as that shell is represented to have " Natibus
prommuMs."

Anodonta imbecilis. — Transvei-sely oblong subovate, very
thin and fragile ; disks convex, green, with darker green obsolete
rays, and three obvious rays on and above the umbonial slope ;
hinge margin rectilinear, terminating before in an angle ; beaks a
little undulated and not elevated above the general curvature ;
from the anterior tip of the hinge margin the slope is rectilinear
to the anterior margin ; within bluish white, iridescent before ;
hinge perfectly rectilinear ; posterior margin rounded.

Length, over one inch. Breadth, over two inches. Convexity,
three-fifths of an inch. Inhabits Wabash River.

By these dimensions, it is evident that the present species is
proportionally broader than any other of our Anodontse. of the same
length. It does not appear to be common in this river, or it may
have been overlooked or rejected as a young Unio by our collec-
tors, without examination. On this account, perhaps, I have only
two specimens, of which the smaller is less than half the size of
the present. It may be a young shell, but if so, in .the adult
state it must be much elongated, inasmuch as its proportions are
now nearly those of the full grown cygriea, Linn. It cannot be
the elongata, Swainson, as the shape differs, and that is a thick
shell with prominent umboncs.

Melania pluristriata. — Turreted; with numerous trans-
verse, elevated lines.

Inhabits Mexico. *

141

Shell oblong-conic, tapering, more or less tinged with rufous ;
whirls eight or ten, without much convexity, with elevated,
numerous revolving lines, about fifteen on the body whirl and
live on those of the spire ; suture of the spire impressed, often
indistinct ; of the body whirl very deeply indented ; apex with a
small truncation ; labrum near the base not remarkably pro-
duced ; base without any rudiment of a sinus ; body whirl slightly
ventricose.

Length, one inch and one-fourth. Greatest breadth, eleven-
twentieths.

It was sent to me from Mexico by Mr. Wm. Maclure. It may
be distinguished from multilineata, Say, by its superior magnitude,
greater elevation of the striae, less prominence of the labrum near
the base, &c.

Melania ntjpera. — Oblong-oval; volutions five, slightly
rounded ; body whirl with about three revolving series of subequal,
equidistant, subacute granules or tubercles not higher than wide,
occupying the superior half of the surface ; second volution with
but two series, remaining volutions with slightly elevated, longi-
tudinal lines, instead of tubercles ; but these are often obsolete ;
spire towards the tip decorticated ; suture not deeply impressed ;
aperture longer than the spire ; sinus of the superior angle pro-
found ; labrum concave, with a callus near the superior angle ;
columella with a slight, obtuse, hardly prominent angle above the
sinus, which is obvious ; labrum not abbreviated above, nor much
produced near the base.

Length, four-fifths ; breadth, less than half an inch. Inhabits
the Wabash River. Var. a. Body whirl with but one series of
of tubercles. Var. h. Body whirl with four or more series of
tubercles.

This species is common in the Wabash River. The spire is
almost invariably so completely decorticated towards the apex,
that no trace of the longitudinal lines remains ; in the young
only are these lines distinct, and even in these they are frequently
wanting.

Melania cancellata. — Shell rather slender, attenuated ]
volutions convex, with about twenty-six reclivate, longitudinal,
elevated lines, crossed by about eighteen revolving ones, the eight
or nine towards the base crowded.

142

Lengtli, more than four-fifths of an inch. Inhabits Florida.

For this shell I am indebted to Capt. Leconte, who informed
me that he obtained it in St. John's River. It diifers from all
our species in the numerous longitudinal and transverse elevated
lines, with the exception of the catenaria, nob., than which it is
of a much more elongated and attenuated form.

Melania semicarinata. — Shell small, rather slender ; spire
attenuated, acute ; the four apicial volutions carinate below ; volu-
tions about eight, somewhat convex; suture moderately impressed;
surface, especially of the body whirl, slightly wrinkled ; within
slightly tinted with reddish brown.

Length, less than half an inch. Inhabits Kentucky.

Occurred in great numbers in a small stream. It may be dis-
tinguished from our other species by its small size, combined
with the existence of a carinated line only in its young state
having increased to four volutions, the carina is no longer formed.

Melania tjndulata. — Shell large, elevated, conic, brownish,
with a broad, equally impressed band ; inferior boundary of the
band elevated and deeply crenate; superior boundary elevated
and sometimes nodulous : volutibns at least eight, not convex :
suture not impressed, hardly obvious, undulated by revolving on
the inferior crenate boundary of the impressed band : labrum, near
the base, much protruded : sinus very obtuse.

Length, one inch and four-tenths. Inhabits the Ohio.

I observed this large species to be abundant in Kentucky
River, when travelling in that State two years since with Mr.
Maclure.

It seems to approach nearest in character to the canaliculata,
nob., but its rough appearance will distinguish it, even at first
sight.

Melania stygia. — Shell robust, ovate conic, black : spire
rather longer than the aperture, eroded at tip; volutions five, hardly
convex : wrinkles obsolete, excepting a few larger ones : suture not
profoundly indented : aperture narrowed at base into a slight sinus
and subaiigulated ; much widest in the middle : labrum much
arquated in the middle.

Length, three-fourths ; greatest breadth, less than half an inch.

A specimen of this shell was given to me by Mr. Lcsueur ;
several were found in Cumberland River, by Dr. Troost. In form

143

it resembles armifera, nob., more than any otber species, but that
shell is armed with tubercles and ornamented by colored lines ; its
suture also is only a simple impressed line.

Melania laqueata. — Shell oblong : spire longer than the
aperture, elevated, conic, acute : volutions, moderately convex, with
about seventeen regular, elevated, equal, equidistant costse on the
superior half of each volution extending from suture to suture, and
but little lower, and becoming obsolete on the body whirl : suture
moderately impressed : sinus obsolete.

Length, four-fifths of an inch.

This species was found by Dr. Troost in Cumberland River.
Aside from a difterenee in form, it may be distinguished from can-
cellata, nob., and catenaria, nob., by being altogether destitute of
elevated revolving lines. The young shell is carinated. I am in-
debted to Mr. Lesueur for a specimen.

Melania obovata. — Shell subovate, dark brown or blackish ;
volutions nearly five : spire remarkably rounded, short : body whir!
with a very obtuse, slightly indented band or undulation a little
above the middle : aperture more than twice the length of the
spire, narrow : labium polished, with a callus above : labrum not
projecting near the base, subrectilinear from the shoulder to the
basal curve, very convex at the shoulder ; base rounded and with-
out indentation.

Animal. — Foot rounded, or rather longer than wide, equally
rounded before and behind ; above yellowish-white, lineated with
black lines.

Inhabits Kentucky River, and some other tributaries of the
Ohio. Length, three-fourths ; breadth, nearly half an inch. Var.
a. Indented band almost obsolete.

The spire, and even a part of the body whirl in old shells, are
sometimes remarkably eroded, as in the M. (anculosa) pr serosa, nob.,
and,indeed, the general appearance is such, that at a little distance,
and without particular observation, it might be readily mistaken
for that shell ; but the form is less globular and the aperture is
altogether different. I found it very abundant in Kentucky River,
in company with that shell and other species of Melania. I also
observed it at the Falls of the Ohio. Lesueur and Troost obtained
specimens in Fox River of the Wabash. When young, the undu-

144

lation is hardly visible, and the shell is often of a dull yellowish
color, which on the larger volutions becomes gradually of the
characteristic color.

Melania INTEGRA.— ^Subglobose, horn color; volutions rather
more than three, rounded, obsoletely wrinkled; spire very short,
less than half the length of the aperture : suture rather deeply im-
pressed : body whirl large : aperture dilated, ovate, acute above :
columella flattened, polished : labrum regularly rounded : base
regularly rounded, without any undulations or sinus : umbilicus
none : operculum obviously spiral.

Length, nearly one-fifth of an inch.

Animal. — Foot longer than wide, rounded behind ; with the ante-
rior angles a little excurved : eyes black, conspicuous ; tentacula
rather long and slender.

Inhabits the Ohio river and many of its tributaries.

This is a very common little shell, abounding more in many
situations than any other species, particularly in the vicinity of the
Falls of the Ohio.

It may readily be mistaken for a young shell.

Melania isogona. — Subglobose, horn color : volutions about
four, rounded, obsoletely wrinkled : spire very short, about one-
third the length of the aperture : suture profoundly impressed, so
as to cause a shoulder on the whirls : aperture much dilated, oval,
being as obtusely rounded above as at base : umbilicus linear, dis-
tinct : operculum obviously spiral.

Length, under three-tenths of an inch. Inhabits Bear-grass
creek, near Louisville.

Not very numerous. It is remarkable by the oval form of the
much dilated aperture, and by the deeply indented suture. In
old specimens, the base is almost acutely angulated.

Melania trilineata. — Subglobose oval, yellowish, more or
less tinged with brown : volutions about four, rounded, somewhat
wrinkled : spire short, rathei' more than half the length of the
aperture : suture not very deeply impressed : body whirl with three
brownish black revolving lines, of which the two inferior ones
are somewhat nearest together, the middle one widest, and the
superior one placed near the suture and revolving on the spire ;
the middle one is concealed on the spire, by the suture : aperture
much dilated, ovate, acute above : labium a little flattened : labrum

145

widely and regularly rounded, without any protrusion near the
base : base slightly angulated, without any sinus or undulation :
umbilicus none.

Inhabits Falls of the Ohio. Length, less than half an inch.
Var. a. Inferior band obsolete. Var. h. Bands obsolete.

This species is allied to the preceding, but is obviously dis-
tinct in its general appearance ; the volutions are destitute of a
shoulder, and the aperture is ovate, acute above. It is a pretty
shell, the bands being very conspicuous, strongly contrasting with
the yellow general color, particularly in the young and half grown
shell.

I obtained about a dozen specimens on the rocky flats of the
Falls of the Ohio, at the lower end of the island which is nearest
to Louisville.

Melania depygis. — Shell oblong conic ovate, not remarkably
thickened : spire as long as the aperture, or rather longer, much
eroded, with a broad revolving band near the suture, occupying
more than half the surface : whirls about five, hardly rounded :
suture moderately impressed : body whirl yellowish, with two
equidistant rufous, revolving lines, of which the superior one is
much broader and its locality a little flatter than the general cur-
vature : aperture ovate, acute, above, moderately dilated : labium
with calcareous deposit, particularly above : labrum not projecting
near the base, nor arquated near its junction with the second volu-
tion : base regularly rounded.

Inhabits Falls of the Ohio. Length half an inch ; breadth,
nearly a quarter of an inch. Var. a. Color dark brown ; bands
obsolete.

I found this species in great abundance on the rocky flats at the
Falls of the Ohio, where they were left by the subsiding of the
river, in company with numerous other shells. In old specimens
the spire is very much eroded ; the eroded part is white.

Paludina transversa. — Shell transverse, depressed, orbicu-
lar : spire convex : whirls three and a half; with numerous minute,
slightly elevated revolving lines : suture not widely indented : body
whirl very convex, short : umbilicus small : operculum pale fulvous-

Grreatest width, two-fifths of an inch. Inhabits Louisiana.

We obtained two specimens in the marshes near New Orleans.
It is much wider in proportion to the length than any other species

146

I have seen, excepting in this respect even M. suhglohosa, nob..
and especially P. intertexta, nob., of which latter, in fact, I at first
supposed it to be the young, in consequence of its rotundity and
the similarity of its capillary lines ; but inasmuch as the number
of its whirls is nearly the same, whilst the magnitude differs so
greatly, I have separated it as a different species.

Paludina intertexta. — Shell subglobose, yellowish-green or
brownish, wrinkled, and with minute, very numerous, obsolete re-
volving, deciduous lines : spire depressed conic, obtuse, truncated^
eroded at tip : volutions nearly four : suture rather deeply indented :
umbilicus closed by the lateral extension of the columella.

Greatest breadth, from four-fifths to one inch ; length about the
same. Inhabits Louisiana.

We collected many of these shells in the marshes near New
Orleans and on the banks of the Carondelet canal. It is remarka-
ble for its globular form and for the numerous obsolete lines which
seem like equidistant deciduous corrugations of the epidermis,
having no effect whatever in modifying the calcareous surface, upon
which it exhibits no trace.

Paludina elongata, Swainson. — Capt. Leconte presented me
with a shell which, he informed me, he found in the river St.
John, Florida. I described it nearly four years since under the
name of multiUneata ; but, recently, being about to publish it, on
a more attentive examination and comparison with a specimen of
the elongata from Calcutta, given to me by Mr. Hyde of Phila-
delphia, I have concluded that it varies from that specimen only
in having the umbilicus a little smaller.

Paludina subpurpurea. — Shell oblong, subovate, olivaceous,
with a tinge of purple more or less intense, sometimes hardly per-
ceptible : spire rather obtuse, terminating convexly : whirls five,
wrinkled, equally convex : suture impressed, but not very pro-
foundly : aperture much widest in the middle, narrower above :
within glaucous, somewhat perlaceous : labrum rectilinear from the
middle upwards : umbilicus none.

Length, about one inch ; greatest breadth, four-fifths of an inch.

An inhabitant of Fox river, an arm of the Wabash. It is very-
distinct from any other species I have seen. The labrum exhibit?
no curvature from the middle almost to its j unction with the penul-
timate volution.

147

Ampluria rotundata. — Shell remarkably globose; length
and breadth equal, dark brown, but becoming olivaceous towards
the aperture : spire but little elevated : suture moderately impress-
ed : body whirl a little undulated instead of being wrinkled ; these
undulations being very perceptible to the finger within the shell ;
aperture within on the margin thickened equally all round, and
fulvous, with a slight groove for the reception of the operculum,
hardly visible but palpable : within somewhat perlaceous ; a little
darker on the columella : umbilicus small, narrow : operculum
calcareous, deeply and concentrically rugose, so as to appear strati-
fied ; nucleus on the side towards the labium sub-marginal.

Length, less, than one inch and four-fifths; greatest breadth,
about the same.

For this interesting species, we are indebted to Capt. Leconte,
of the Topographical Engineers, who informed me that he found it
in St. John's river, in Florida.

It is most closely allied to the A. glohosa, Swainson, a native of
the rivers of India. But that shell is rather less globose, and does
not appear to have the almost regular, but slightly elevated and
very numerous undulations so perceptible towards the aperture on
the body whirl of this species ; which has also a few hardly per-
ceptible, distant, brownish bands, particularly towards the base.
It may, however, be only a variety of that species.

Ampullaria depressa. — As the name depressa, of the Ap-
pendix to Long's Expd. p. 264, is preoccupied by Lamarck for a
fossil species, it may be changed to paludosa.

Ampullaria elagellata. — Shell subglobose, olivaceous
brown, with 15 or 16 revolving, dull reddishbrown, slender bands :
spire conic, moderately elevated, acute: body whirl regularly
rounded, more obviously undulated or obtusely wrinkled near the
aperture : umbilicus free, obvious : labrum a little dilated : within,
reddish brown : labium, columella, and the margin of the labrum
white : operculum horny.

Length, over one inch and a half; greatest width, one inch and
two-fifths. Inhabits Mexico.

Occurs in plenty a short distance below Vera Cruz. We found
them immediately behind the sand-hillocks of the coast, in situa-
tions which, in rainy seasons, are covered witli fresh water. We
did not see a living specimen ; they were mostly decorticated and

148

bleached. Than A. depressa, nob., (changed to paludosa, nob.,
as the name is preoccupied,) it has a more elevated and acute
spire, larger umbilicus and more regularly rounded body whirl. I
am unacquainted with the A. linearis, Perry, which he supposes
to be a native of the coast of North America.

Valvata humeralis. — Shell subglobose, depressed: spire
convex, not prominent : whirls three and a half, with the shoulder
depressed, plane ; wrinkled across, or rather with slightly raised
lines : aperture appressed to the penultimate whirl, but not inter-
rupted by it ; umbilicus rather large.

Greatest breadth, less than one-fifth of an inch. InTiabits
Mexico.

Differs from V. sincera, nob., of the North-west Territory, in
being more depressed, and in having a shoulder or plain surface
near the suture. The umbilicus is larger than that of the V. pisci-
nalis, Mull., and the spire more depressed ; that species is also des-
titute of the depressed shoulder.

Lymneus caperatus. — Shell suboval, a little oblong, obscurely
yellowish horn color : spire half the length of the mouth : apex
acute : whirls slightly wrinkled across, and with very numerous,
equal, subequidistant, elevated, minute, revolving lines : suture not
very deeply impressed : aperture rather dilated; fold of the labium
not profound.

Inhabits Indiana.

The remarkable character of this species consists in the numer-
ous revolving lines with which the surface is marked ; but these
are so minute as to require the aid of a magnifier to bring them to
view. It was found on land subject to inundation, near New Har-
mony, by Dr. Troost.

Lymneus attenuatus. — Shell elongate tuiTeted, somewhat
translucent : spire slender, attenuated, acute : whirls six or seven,
with but a very slight convexity ; wrinkles more distinct towards
the aperture : body whirl, measured at the back obviously less than
half the total length.

Length, one inch. Inhabits Mexico.

This species abounds in the ditches and ponds in the vicinity of
the Capitol. It is more nearly related to L. reflexus, nob., than to
any other known species of North America ; but it is only neces-
sary to compare the two in order to perceive a wide difference

149

between them. The present is smaller and proportionally more
slender, and the spire is more attenuated.

Note. — Bulla fluviatilis, nob., seems to be no other than the very
deceptive young of our common Planorbis.

Anoylus tardus. — Shell conic depressed : apex behind the
middle obtuse, rounded, inclining backward but not laterally : line
from the apex to the posterior tip rectilinear ; line from the apex
to the anterior tip arquated : aperture oval, not distinctly narrowed
at one end.

Length, a little over three-twentieths 4-25 ; breadth, one-tenth
of an inch.

Differs from A. rioularis, nob., which has the apex leaning
towards one side, and the aperture narrower at one end. It is less
elongated than fluviatilis, Drap., which has an acute and laterally
inclined apex.

It inhabits the Wabash River.

[No. 6. Transylvania Journal of Medicine, vol. 4, p. 525, etseqq. 1831.]

UnIO INTERRUPTCS, UnIO GLEBULUS,

" nexus, ^ " declivis,

Unio lapu,lus.

[The descriptions of these species were afterwards repeated fn the
"American Conchology." For the sake of greater convenience they
will be found under that head. They were not included in Mrs. Say's
" Descriptions." — Ed.]

[No. 7. American Conchology.]

[Am. Con., part 1, 1836.]

AsTARTE. — Shell suborbicular, generally transverse, equivalve,
ingequilateral, closed entirely ; hinge with two strong, distinct, di-
verging teeth on one valve, and on the other two very unequal
teeth and a lateral obsolete one ; ligament exterior ; muscular im-
pressions two, and a minute one above the posterior impression,
almost confluent with it ; impression of the mantle simply arquated,
distinct.

* [No description already included in my reprint will be repeated here,
but any additional remarks, &c., will be given. — Ed.]

150

Obs. A genus, containing but a small number of species, in-
stituted by Sowerby under the name we have adoptod. Lamarck
appears not to have been aware of the previous existence of this
genus, when he published it under the name of Crassina in his
Anim. sans Vertebr. He referred it to his Nymj)hace,e& teU\naire$ ;
but we agree with Sowerby, in the opinion, that its proper place is
with his Conqites marine ; from all of which it is distinguished by
its cardinal teeth and interior impressions.

Blainville in his " Manuel de Malacologie et de Conchyliologie "
places it as a division of his genus Venus, under the following
characters :

" Solides, epaisses, suborbiculaires, subequilaterales ; deux tres-
grosses dents divergentes sur une valve, et deux tres-inegales sur
I'autre ; les impression es musculaires reunies par une ligule sans
sinuosite posterieure." He informs us that Defrance has announced
the existence of eighteen fossil species, and we described two in the
Journ. Acad. Nat. Sci.

AsTARTE CASTANEA. — Specific character. Beaks nearly cen-
tral ; epidermis chestnut-brown.

Venus castanea, nobis. Jour. Acad. Nat. Sci., vol. ii. p. 273.

Ohs. It is longer in proportion to its breadth than the danmoni-
cnsis of Montague, and is destitute of the fine and regular striae,
with which the oUiquala is marked. PI. 1.

Pandora. — Shell transversely oblong, insequilateral, inequi-
valve, unattached, regular, somewhat rostrated ; left valve flattened,
with from one to three teeth extended upon the inner surface of the
shell, with a fosset for the ligament ; hinge margin inflected ; right
valve convex, teeth one less than in the left valve, with the corres-
ponding fosset; ligament internal, attached to an elongated fosset
or cicatrice, which inclines towards the anterior margin ; miiscular
impressions two, distant, lateral.

" Animal very much compressed, elongated, in the form of a
sheath, by the union of the edges of the mantle and its continua-
tion with the tubes, which are united and very short; foot small,
thicker before, exserted by a large slit in the mantle ; branchire
pointed backwards and continued into the tube." — (Blainville.)

Ohs. The hinge teeth extend on the inner surface of the shell
in some degree like those of Placuna, to which genus this seems
to be allied, both by the position of the teeth and the perlaceous

151

consistence of the shell ; but it is eminently distinguished by having
two muscular impressions. Lamarck, who first characterized the
genus placed it next to Corlnila, chiefly, perhaps, in consequence
of the inequality of its valves.

Two species only are described by Lamarck, the ineequivalvis,
Linn., and the ohtusa, a newly described species. Sowerby has
added another, imder the name of flexuosa. According to Blain-
ville, two fossil species have been discovered by Defrance. The
animal is so similar to that of Solcn, that Poll has referred it to
the same genus, which he calls Hyipogea.

Pandora trilineata. — Specific character. Hinge margin
bilineate from the beak to the tip; valves not very inaequal.
PL 2.

Pandora trilineata, nobis. Journ. Acad. Nat. Set., vol. ii.
p. 26L

Oliva. — Shell subcylindric, oblong, smooth, more or less polish-
ed ; epidermis none ; spire short ; suture canaliculated, the edge
of each volution extending a little upward, canal bounded above
by a revolving, carinate callus ; body whorl near its base with a
slightly elevated band, beginning below the middle of the aperture
and revolving to the base of the labrum ; aperture elongated ',
labrum and columella with calcareous deposite, much striated, striae
on the latter more elongated ; base deeply emargiuate ; operculum
none.

Ohs. The smoothness and polish of these beautiful shells are
no doubt owing to the extension of the smooth surface of the
mantle of the inhabitant, over their whole exterior. The animal
is not yet well known, but Lamarck supposes it to be carnivorus. It
is marine.

Of all the species figured in the books, and existing in the col-
lections, Linne formed but about two species, which he referred to
his genus Valuta under the names of olioa and porpltyra. Bru-
guiere applied to them the present generic name, which was adopt-
ed by Lamarck, who, with his usual acute perception of natural
differences, described more than sixty species, among which are a
few that exist only in the fossil state, and according to Blainville^
thirty-two new species have been added by M. Duclos, from the
coast of New Guinea.

This genus is closely allied to AnciUa, which, however, is des-

152

^itute of strice on the labium and the spiral canal is completely
filled up. From Terehellnm, to whicli it is also allied, it may be
distinguished by the striated labium and columella, and the elevated
band at the base of the body whorl, and from Mitra and Valuta
by the canaliculated suture.

Oliva literata, Lam. — Specific character. Shell with nu-
merous angulated brownish lines and two bands of chestnut-brown
ones.

Oliva literata, Lam. Atr. dii Mus., vol. xvi., p. 315 ; and
Anim. sans Vertehr., vol. viL, p. 425.

Oliva. Encycl. Meth., pi. iiQ2,fig. 1, a, h.
Desc. Shell with a pale yellowish-white ground color, thickly
covered with cinereous-rufous angulated lines, leaving distinct tri-
angles of the ground color ; on each side of the middle is a broad
baud, occasioned by the angulated lines being there of a deeper or •
chestnut-brown color ; the angulated lines at the upper edge of
the volutions are fasciculated and of the same color of the bands.

Ohs. We are far from being certain that this is absolutely the
literata of Lamarck, although it agrees perfectly, except in being
smaller, with the figures above quoted, to which he' refers. He
supposed his specimens to be native.; of the East Indies. However
this may be, and although we formerly described it under another
name, we think it more prudent to consider it as indicated by
Lamarck's description and the figures of the Encyc. Methodique.
It is rather common on our Southern coast. PI. 3.
Unio. — Shell unattached, generally transverse, equivalved, ine-
quilateral ; cardinal teeth one in each valve, irregular, generally
striated, simple or biparted ; an elongated lamelliform to'oth on the
anterior hinge margin of the left valve, and two similar teeth on
the corresponding margin of the right valve ; muscular impressions
two principal ones; ligament exterior.

Ohs. In North America the shells of this genus excel those bf
any other country in magnitude, beauty and diversity of species.
They arc altogether inhabitants of fresh water,. and we have hardly
a rivulet in the Union in which they are not to be found. Many
of them are of a beautiful perlaceous color and consistence, and wc
are informed that some of the very thick ones of the Ohio, have
been, at Pittsburgh, successfully turned into buttons and orna-
ments.

153

This genus is closely allied to Dipsas, Leach, Hyrixjb and Iridina,
Lam., Alasmodonta, nob., and Anodonta, Brug. But the former
has lamelliform teeth only ; Hijria Has lamelliform teeth on both
sides ; Iridina and Anodonta are destitute of teeth and Alasmo-
donta is destitute of lamelliform teeth. To this exposition we may
add, as more remotely allied, the Megadesma of Bowd., which has
two cardinal teeth in one valve and three in the other, with a re-
mote indistinct tooth on each side ; characters that indicate an ap-
proach to Cyrena. Some of these genera are so intimately linked
together by intermediate species, particularly the Unio and Ano-
donta, there being one or more in our streams, that.it is somewhat
difficult to determine in which of the two genera it ought to be
placed. Consequently, those naturalists who advocate the union of
such genera as are connected by intermediate species, will be com-
pelled to unite these, and on the same principle they must reject
great numbers of genera long since firmly established.

Unio triangularis, Barnes. — Specific character. Shell tri-
angular, very convex ; anterior margin forming a right angle with
the disk.

Unio triangidaris, Barnes. Silliman's Journal, vol. 6, p. 272,
pin,fig.ll.

Unio ctmeatus, Swainson. Tilloch's Magazine, December, 1823.

Desc. Shell triangular, very convex, gaping at the extremities ;
anterior margin veiy much flattened, forming a right angle with
the disks ; having longitudinal slightly elevated lines crossing the
transverse wrinkles ; ligaments very short ; anterior tip angulated ',
posterior margin rounded, destitute of distinct lunule ; epidermis
pale yellowish-olivaceous, radiated with green, interrupted into
short lines and spots, which are sometimes sagittate, and disappear
on the margins of the old shell.

Obs. It is highly probable that the present species is the cunea-
tus of Swainson ; it certainly agrees with his description. But this
is of little consequence, as Mr. Barnes' name has the priority, and
he has also preoccupied the name which Mr. Swainson has chosen,
Mr. Barnes correctly remarks that this shell in shape resembles
Alasmodonta marginata, nob. The extraordinary depressions of
the anterior margin is very characteristic and readily distinguishes
it from other species. As the shell increases in age, this margin
becomes a little elevated at tip, as is exhibited in our figures, and

13

154

the position of the beaks varies a little. The umbonial slope is
often elevated into a rib, and the striae occupy a considerable part
of the shell and become so profound as almost to denticulate the
edge of the shell. PI. 4.

Unio sulcatus, Lea. — Specific character. Transversely sub-
quadrate ; posterior margin not extended beyond the umbones.

Unio sukatus, Lea. Trans. Amer. Philos. Soc, vol. 3, N. S.

Desc. Shell very obliquely transverse, subquadrate ; with an
indented groove extending from the umbo to the anterior and
anterior basal margins, between which the edge is somewhat re-
tuse ; epidermis yellowish-olivaceous, with radiating, deep green,
more or less undulated lines ; summit near the posterior extremity,
prominent ; anterior margin with two obtusely rounded angles, a
little gaping ; cavity of the hinge membranes behind the summits
deeply excavated, nearly as long as wide, distinctly angulated be-
hind ; posterior margin regularly rounded, remarkably short, hardly
extending beyond the line of the posterior tip of the umbo ; within
perlaceous-white, more particularly iridescent before ; teeth regular,
anterior cardinal tooth parallel with the lamelliform tooth, which
is very slight arquated ; posterior muscular impression deep ; sinus
of the cartilage very slight, regular ; cavity of the umbo not deep,
its muscular impressions obvious; palleal impression somewhat
truncate before, and not extending anteriorly beyond the line of
the muscular impression.

Var. a. Within, except on the anterior margin, purple or livid.

Ohs. It occurs in the Wabash and Ohio rivers. In order to
avoid confusion, I may mention that the present species is in many
of the European collections, sent by me within the last five years,
under the name oi fiagellatus. PI. 5.

Unio RIDIBUNDUS. — Specific character. Subquadrate ; emar-
ginate before and denticulated on the anterior basal angle.

Desc. Shell transverse, subquadrate oval, olivaceous, radiate
with capillary deep green lines ; summits somewhat prominent,
nearly terminal : cavity of the hinge membranes oval, rather larger
behind the beaks than broad : posterior side veiy short : anterior
side with a groove, obsolete on the umbo, but becoming deeper to
the anterior edge, which is consequently emarginate a little below
its middle; a little gaping; the inferior angle somewhat more
prominent, rounded and denticulated : anterior muscular impression

155

very deep : palleal impression emarginate opposite to tlie denticu-
lated angle : above this angle also, tlie concavity is abruptly more
concave, so as to form a definite dilated groove.

Var. a. Within deep reddish purple.

Obs. The remarkable character of the anterior basal angle or
lobe of this species, renders an extended and more particular
description unnecessary. In the figure of the annexed plate, we
have brought this character particularly into view, by a delineation
of the front of the shell, and two or three series of the teeth are
visible in some specimens, like varices in the univalves, on the
surface of the shell, fringing the deeper undulations or wrinkles.
[We may remark that in our figure these teeth have too much of
a serrated appearance ; they are in reality more tooth-shaped,
though slender.] It has considerable resemblance to the sulcafus*
Lea, in general form, brevity of the posterior side, summits, cavity
of the hinge membranes and radiated surface, but the denticulated
anterior edge, the more acute anterior groove and other subordinate
characters, amply distinguish it. It is a small species, even smaller
than the sulcatus.^

A remarkable and gigantic variety occurs in Cumberland river;
a specimen is rather more than two inches wide and the radii are
interrupted into spots. It may prove to be a distinct species when
more specimens are obtained for comparison, and it may in that case
be distinguished by the name of perplexus. For a specimen of
it I am indebted to Mr. Lesueur. PI. 5.

Unio monodonta. — Specific character. Transversely elon-
gated; inner margin whitish or livid; lateral teeth obscure.

Desc. Shell transversely much elongated, slightly arquated,
blackish-brown; umbonial slope (Swainson) widely rounded, not
abruptly elevated : umbo placed far back, not prominent above the
general curvature ; hinge and basal margins a little arquated, pa-
rallel : anterior and posterior margins regularly rounded : within
perlaceous, with an opake whitish or livid margin : primary teeth
simple, small : lateral teeth very imperfect ; that of the right valve
with only an impressed, short line, instead of the usual deep recipi-
ent fi^ssure.

I obtained numerous specimens at the Falls of the Ohio, 'on the

* [I change y?a5re?/a^us to sulcatus, in accordance with an erratum of the
author. — Ed.]

156

rocky flats wliicli are exposed in a low state of the water. Its elon-
gated form is somewhat similar to that of the rectus. Lam. ; but it
is much thinner, more widely rounded before, and more compressed,
particularly anteriorly. Its teeth distinguish it from any other
species hitherto described. Old shells are very much decorticated
and eroded ; and in some individuals, the impressed line on the lat-
eral tooth is hardly perceptible : still it cannot for one moment be
mistaken for an Alasmodgnta, as the habit is quite different. Mr.
Lesueur has presented me with a specimen found in the Wabash.
PI. 6.

Delphinula. — Shell spiral, subdiscoidal or conic, lunbilicated ;
whorls rough, foliaeeous or angulated on the surface ; aperture orbi-
cular, entire ; labia united, often fringed or furnished with a peris-
tome.

Ohs. Linn6 referred the laciniata and distorta, the only species
known to him, to the genus Turbo, in consequence of the rotundity
of the aperture ; but Lamarck separated them, and with a number
of new species, chiefly fossil, formed the present group. Lamarck
observes that they " evidently approach the Scalarise" and among
them we also see species, of which the spire is loose, and the volu-
tions separate. In addition to the above mentioned species, Lamarck
gives one or two others and about ten fossil ones. Defrance enu-
merates about thirty species.

Delphinula? lax a. — Specific character. Whirls all separate
and distinct. PI. 7.

Delphinula laxa, nohts. Jcnirn. Acad, Nat. Sci., vol. 5, p. 207.
Melania. — Shell turrited, rather thick, covered by an epi-
dermis ; spire generally elongated; aperture ovate or oblong, longer
than broad, acute above; labrum simple, acute, prominent near
the base and rather abruptly retracted at its junction with the base
of the columella, and not united above to the labium ; columella
destitute of a fold, arquated towards the base ; operculum corne-
ous ; umbilicus none.

Obs. Before Lamarck perceived the necessity of establishing
this group, some of the species were variously arranged. Linn^,
Lister, Schroeter, and others, considered them as belonging' to
Helix ; Muller to Nerita and JBuccimmi ; Brugui^re to Bulimus,
and Chemnitz referred one species to Stro^nbus. The genus differs
from Helix, Lymneus, &c., by having an operculum as in Palvdina,

167

Ampularia, and Valvata, and from these, in addition to other
differential traits it may be distinguished by the disunion above of
the labia). It strongly resembles Melanopsis, Pirena and Potam-
ides, but these are distinctly and unequivocally emarginated at
base.

The animal respires water j it has a short, conic-cylindric, obtuse
rostrum; two acute tentacula having the eyes at their exterior base ;
foot short and obtuse.

They are inhabitants of fresh water, chiefly in the tropical re-
gions ; but many species are very abundant in the rivers, lakes and
small streams of the United States. No recent ones have been
found in Europe, but several have occurred fossil in comparatively
recent formations. No fossil species have yet been found in this
country. Lamarck described sixteen recent and twelve fossil spe-
cies ; but Defrance enumerates thirty-six species.

Melania nupera,* — Specific character. From one to four or
more revolving series of tubercles.

Ohs. It varies in the number of its series of tubercles, some
specimens having but one, and others, though these are rare, as
many as five or six. Plate 8. Middle figure exhibits the young
shell.

Melania depygis.* — Specific character. Body whorl yellow-
ish, with two equidistant, revolving, rufous lines.

Ohs. It varies a little in color, and a few occurred, of which
the color is fuscous, the bands being obsolete: PI. 8, lower figures.

Lutraria. — Shell equivalve, inasquilateral, transversely oblong
or subovate, gaping at the extremities, particularly at the posterior
extremity ; cardinal teeth two, of which one is doubled in the
shape of a V, the other simple, with a large deltoid cavity situated
obliquely near the teeth ; lateral teeth none ; ligament internal, in-
serted in the cardinal cavities, not visible when the shell is closed ;
mascular impressions two, lateral, remote, simple ; impression of
the mantle extending to the muscular impressions and having a
large and profound sinus extending nearly half its length.

Obs. Lamarck separated this group from the Linnaean Mactrse,
from which it is essentially distinct by the absence of lateral teeth

* [Mr. Say makes no reference to the previous descriptions of this spe-
cies in N. H. Diss. — Ed.]

158

as well as by other less striking characters. The animal has a
large fleshy cylinder, containing two tubes, one for respiration and
the other evacuation, situated at the posterior extremity. The
foot is small and compressed, placed at the opposite extremity or
near it.

It is a littoral genus, inhabiting estuaries and near the mouths
of rivers.

Blainville unites this genus with Ligula, Leach, under the
ereneric name Lutrkola. Lamarck describes eleven recent and
one fossil species.

LuTRARiA LINE AT A. — Specific character. Posterior margin
with a reflected edge and submarginal carinated line.

Lutraria lineata, nobis. Jour. Acad. Hat. Sc. vol. 2, p. 310.

Lutraria papyracea ? Lam. Anim.sans Vertebr. vol. 5, p. 470.

Ohs. The elevated line of the posterior submargin and the re-
flected posterior edge are very characteristic, distinguishing this
species from all others, excepting the figure 2 of the plate on
Lutraria in the second volume of Mr. Sowerby's excellent work
on the " Genera of Recent and Fossil Shells." Our shell is much
shorter on the posterior end than his figure, which he refers with
doubt to the pa2yyracea of Lamarck; a difi"erence which, however,
may be attributable to an inequality of age, as it becomes more
elongated anteriorly in the older' shell. Whether or not the present
species is the same as that of Lamarck we cannot at present de-
termine, but it is without doubt closely allied to it. Still, how-
ever, it does not agree with the figure in the Eneycl. Meth. 257,
fig. 2, a, b, quoted by Lamarck. PI. 9.

Paludina. — Shell fluviatile, conical, subovate or suboval, cov-
ered by an epidermis ; spire moderate ; whorls convex ; aperture
longer than broad, angulated above, simply rounded at base ; la-
brum simple, acute, united above to the extremity of the labium ;
labium simply arquated ; operculum corneus or coriaceous, subor-
bicular, slightly angulated above.

Ohs. The species of this genus were widely separated from each
other by former authors, and referred to the Genera Helix, Turbo,
Bulimus, Nerita, and Ci/clostoma ; but Lamarck selected and em-
bodied them under the present designation, and they now consti-
tute a natural group.

159

Tliey may be distinguished from Ci/chstoma by the simple la-

brum, as well as by other characters of the shell, as also of the

animal, from Jlelania by the simple curvature of the labrum at

ott- base, and from Valvata by the form of the aperture which is

not angulated above in that genus.

The animal has two linear-acute tentacula, with the eyes at their
exterior base ; anterior part of the body with a small membrana-
ceous wing on each side, the right one is " recurved in a small
canal, which introduces the water into the respiratory cavity ;"
" the branchiae are composed of parcels of filaments, which are
attached to the sides of the branchial cavity," and are altogether
internal, a character which distinguishes them from the animal of
Valvata.

They inhabit fresh waters and are very common in almost all
our lakes and streams. As they respire water, they do not so
uniformly reside near the water's edge as the Lymnese, which
respire air only. Like them, many of the species, if not all, have
the power to swim at the surface in a reversed posture, the foot
being applied to the surface, and the shell being downward.

Lamarck describes seven recent species, and Defrance enumer-
ates five fossil ones.

Paludina decisa. — Specific character. Aperture more than
half the length of the shell, within bluish-white.

Cochlea virginiana e flava viridescens, non faciata, Lister.
Conch, tab. V21,fifj. 27.
Petivcr gazophyl, tab. 10Q,fig. 18.

Paludina decisa, nobis. Nicholson's Encycl. {Amer. Edition^)
article Conchology, pi. 2, fig. 6.

Obs. The species is very common in various parts of the Union.
Dillwyn informs us that Muller and others have incorrectly quoted
Lister's figure for their Helix angularis. PI. 10, the upper and
lower figures.

Paludina vivipara, Lin. — Specific character. With about
three reddish-brown revolving lines.

Cochlea vivipara fasciata. Fluviatilis, Lister. Conch., tab.
126, y?^. 26.

Helix vivipara, Linn., Gmel. and others.
Nerita vivipara, Muller, Verm., p. 182.
Cychstoma vivipara, Draparn., pi. 1, fig- 16.

160

La vivipare a handes, Geoff. Cuvier.

Paludina vwipara, Lam. Am'm. sans Vertehr., vol. 6, 2nd
part, p. VIZ. Nobis. Nichokou^s Enc.

Ohs. This appears to be one of the many species, that are com-
mon to North America and Europe. And though the specimens
from the two continents differ a little, yet this difference is so
slight as not to be specific. Cuvier remarks that ''the female
produces living young, which are found in its oviducts, in the
spring, in every state of development. Spallanzani assures us,
that the young, taken at the moment of their birth and nourished
separately, reproduce without fecundation, like those of the Aphis.
The males are nearly as common as the females ; their generative
organ is exserted and retracted, as in Helix, by a hole pierced in
the right tentaculum, which causes this tentaculum to appear
larger than the other. By this character the male is easily
known."

The vivipara is far less common than the decisa, and seems to
be more usually found in the southern part of the Union. Mr.
Elliott of Charleston sent me two specimens from the banks of St.
John's river, Florida, and Capt. Leconte presented me with one,
which he obtained at Lake Gleorge on the same river. PI. 10?
the two middle figures exhibit the brownish banded var.

[Am. Con. vol. ii. April, 1831.]

Anodonta. — Shell equivalve, inequilateral, transverse, regular ;
hinge margin linear, without teeth having a sinus before ; ligament
external, elongated, terminating in the anterior sinus ; muscular
impressions two, remote, posterior one compound.

Obs. These are shells of rather large size, residing in fresh water
streams and lakes. They are generally perlaceous within and green-
ish on the exterior. Although the genera Anodnnta and Unio are
closely allied, yet the species were widely separated by Linn6, who
referred those of the present genus to Mi/tilm, whilst those of Unio
he associated with the Mi/x ; but an arrangement so artificial could
not escape BruguiSres. He perceived their affinities, and grouped
them under the above mentioned denominations. Several other
allied genera have been formed by subsequent naturalists, distin-
guished from the present by the existence of either cardinal or

161

lamellar teeth, with the exception, however, of Iridma of Lamarck,
which has an elongated, linear, crenulated hinge, and was placed by
Brugui^res in Anodonta, to which, indeed, it is intimately linked
by the I. nihtica. Ferussac, in his Tableaux Syst., included all
the genera of this family in four, viz., Anodonta, Hyria, Unio, and
Castalia. Sowerby has since proposed to retain Unio only, and, as
Ferussac had already done, to consider the other genera as sub-
genera.

Blainville describes the animal nearly thus : Body large, thick,
more or less oval ; mantle thickened on the margin, simple or
fringed, and excepting on the back, open all around ; anus oval,
distinct; a kind of small incomplete tube, furnished with two
ranges of cirri, for the respiratory cavity ; foot very large, com-
pressed, lamelliform.

The principal naturalists and anatomists have been decidedly of
opinion that the animals of this family are hermaphrodites ; but
Mr. Prevost, of Geneva, affirms that he observed, in some individ-
uals of the Unio pictorum, the existence of spermatic animalculse,
which he could not perceive in those which contained eggs. He
therefore inferred that the sexes were distinct. This led Blainville
to a re-examination of the subject: he dissected about forty indi-
viduals of the genera Unio and Anodonta, without discovering any
indications that could lead him to suppose the existence of the male
sex ; still, however, he is in doubt, and we are very much inclined
to believe, with Ferussac, that Prevost may be right, but that more
observations and observers are required fully to establish this dis-
puted point, although Baer has gone far towards even this object.
Treviranus also made some interesting observations on this subject,
an account of which he published in the Zeitsch. fur Physiol, in
1824. He was of the opinion that the same organ produced both
the ova and the fecundating fluid. He, however, remarks that
he found, at the season of excluding their eggs, many that were
entirely destitute of them.

Some naturalists have changed the designation of this genus to
Anodon, as being more rigidly correct.

Anodonta suborbiculata. — Specific character. Suborbicu-
lar, a little winged.

Desc. Ovate-orbicular, rather compressed ; pale olivaceous
tinted with flesh color ; with very slender, almost capillary^ and

162

very numerous, obsolete greenish radii ; sometimes with more or
less obvious, transverse, yellowish bands' towards the base ; beaks
not elevated above the general surface, with two or three rows of
very small tubercles : hinge margin nearly rectilinear, compressed
behind, and anteriorly compressed almost into a wing : ligament,
particularly in the young specimen, concealed : posterior margin
rounded : anterior margin a little prominent, obtusely angulated ;
basal margin much arquated : within undulated almost as obvi-
ously as on the exterior ; pale bluish, varied with pale flesh color,
and somewhat iridescent before and behind : cicatrices slightly
impressed.

Length about four inches. Breadth five and three-tenths. Con-
vexity nearly one inch and three quarters.

A large and fine species. Some time since, Mr. 0. Evans
obtained an individual, which I hesitated to publish as new, think-
ing it might possibly be a young remote variety of the A. grandis,
nob., but subsequently, having received adult and perfect speci-
mens from Mr. Evans, I found that it is uniformly longer, more
rounded, much more compressed, and having a different aspect.
It is found in ponds, near the Wabash river, but rarely, if ever, in
the river itself, as it prefers still water and a muddy bottom. In
form it approaches nearer to orbicular, than any other species that
we have seen described.

An American conchologist was of the opinion that all our Ano-
dontas are referrible to one species ; but we conceive that the
present species, cannot with more propriety be united with the
cataracta and marginata, nob., not to mention the more elongated
species, than the various species of Unio can be considered as no
other than U. picta, L. PI. 11.

NucuLA. — Shell transverse, equivalved, inequilateral ; summits
contiguous ; hinge with a primary, more or less triangular fosset for
the reception of the ligament, with an anterior and posterior series
of small, inserted, numerous, pectinate teeth, interrupted at the
summit by the fosset ; ligament internal, very short, inserted into
the fosset ; muscular impressions two, simple.

Ohs. A genus connected with Area, Pectuncidus, Cuculkea,
and Trigonia, but eminently distinguished by the ligament being
interior ; which, as has been remarked by Sowerby, proves their
relation to the Mactracese. Many species are known. Lamarck

163

described six recent and the same number of fossil species ; Sow-
erby four fossil and one recent ; Defrance enumerates twelve fossil;
and we have published two recent and two fossil species. Of all
these the tcllinoides, Sowerby, and lanceolata, Lam., appear to be
the largest.

The inhabitants are thus described by Blainville : body subtri-
quetrous ; mantle open on its inferior half only, the margins entire^
denticulated on the whole length of the back, without posterior
elongations ; foot very large, thin at its origin, dilated in a large
oval disk, the margins of which are furnished with tentacular digi-
tations ; anterior buccal appendices very long^ jwinted, rigid, and
applied against each other like a kind of jaws; the posteriors
equally rigid, and vertical.

NucuLA LiMATULA. — Specific character. Oblong-ovate, ros-
trated, pellucid ; beaks subcentral, not elevated ; margin entire.

Desc. Shell transversely elongated subovate, green olive, nearly
pellucid, smooth, polished, with slight indulations of increment :
beaks not prominent above the curve of the hinge margin ; hinge
margin anteriorly abruptly compressed ; the compression not reach-
ing the tip ; rectilinear nearly to the tip which is a little recurved ;
posteriorly almost regularly, but obtusely arquated : posterior mar-
gin regularly rounded : anterior margin somewhat rostrated, not
truncated : within a little perlaceous : margin entire : line of the
teeth slightly interrupted and a little angulated at the fosset, ex-
tending more than two thirds of the length of the shell, rectilinear
before and behind : teeth prominent, numerous, acute, much angu-
lated at their bases and longer than the breadth of their bases :
fosset triangular, short, rather small, and but little oblique.

This pretty species was presented to me by Nuttall as having
been taken from the stomach of a fish at Nahant, Massachu-
setts.

It resembles the N. fiuviatilis, Schrbter, and the N. rostrata
Montague, but the rostrum is not truncated, and the summit is more
central than in those species. It is still more closely related to iV.
Isevis, nob., but it is proportionably a little longer, and in that spe-
cies the posterior series of teeth is a little arquated, and the com-
pressed anterior hinge margin extends quite to the tip. I must
say, however, that I have seen but a single specimen, and but a
single valve of the present shell. The iV. arcttca, Gray, which

164

this might be supposed to resemble, is said to be -^ postice brevi,
obliqu^ truncato." PI. 12.

For comparison I add, from the Journal of the Academy of Nat-
ural Sciences, the following description and figure of W. Isevis, and
also those of a smaller and quite distinct fossil species.

[NucuLA L^vis, pi. 12, right hand figure, and npcula concentrica, pi.
12, left hand figure, being fossil species, I have not given the descriptions,
J. A., iv. p. 141.— Ed.]

Unio ellipsis. Lea. — Specific character. Shell very oblique,
suboval ; summit prominent, as long as the posterior side.

Unio ellipsis, Lea. Trans. Amer. Phtlos. Soc. (new series') vol.
B, pi 4, fig. A.

Desc. Shell veiy oblique, oval-subovate, ventricose, ponderous :
disk convex, lines of growth deeply impressed, somewhat undulating
the surface ; yellowish-olivaceous, more or less radiate with green,
particularly before ; never spotted ; the old shell uniform brown or
fuscous : margin regularly arquated, even at the anterior tip : sum-
mit prominent, as long as the posterior side : posterior side re-
markably short : cavity of the hinge membranes profound, much
dilated between the summits and not extending posteriorly beyond
the line of the summits ; visible portion triangular, its posterior
line transverse, slightly arquated, widest : within white, perlaceous,
iridescent before : teeth large, prominent, the cardinal anterior of
the right valve and both of the left valve parallel to the lateral
teeth, which are a little arquated, those of the right valve united
at tip and even after the union a little more elevated than the
surrounding surface : sinus of the cartilage, regular, definite :
cavity of the umbo not deep, its muscular impressions very distinct :
posterior muscular impression remarkably deep, subobconic : palleal
impression anteriorly arquated, hardly extending beyond the line
of the muscular impression.

Obs. This species is not uncommon. The young shell which
we have represented in the plate has a difibrent coloring from the
old specimen, which is of a uniform dark, or even blackish-brown,
the radii being entirely invisible. It varies in its radii, some being
radiated over the whole surface, others having a capillary radii
only on the anterior side and others being entirely destitute of
radii at all ages. Another variety is tinged with rosaceous, especi-

165

ally ou the hinge laminae. In its youth it somewhat resembles
the sulcatus, Lea, but is distinguished by many characters, and re-
markably by being destitute of any sulcation anteriorly. The
largest one I have seen was nearly four inches in its greatest
diameter ; but this is gigantic for the species. PL 14.

Unio subtentus. — Specific cJiaracter. Transverse ; anterior
dorsal margin sculptured with small elevated costse.

Unw subtentus, nobis. Jour. Acad. Nat, Sc. vol. 5, ^j. 130.

Obs. In general outline this shell has some resemblance to U.
purpurcm,* nob. ; but is distinguished by many characters, and
more obviously by the character of the anterior costated margin.
PI. 15.

Unio undulatus, Barnes.f — Specific character. Transversely
undulated ; umbo literate.

Unio undulatus, Barnes. Silliman's Journal, vol. 6, p. 120, pi. 2.

Desc. Transversely oval, somewhat oblong, with large, distinct
undulations, three or four in number, directed towards the anterior
margin and not proceeding directly from the umbo : surface with a
few abbreviated, longitudinal lines, placed without any regularity :
umbo placed far backward, not prominent, hardly elevated above
the general curvature, more or less literate with short, irregular
lines, or slight elevations : hinge margin compressed, nearly recti-
linear, prominently angulated or subalated at tip, in the more per-
fect specimens with numerous, connected, regular lines, curved to
the edge and undulating it : anterior margin rectilinear from the
extremity of the hinge margin to the rounded inferior half, and
undulated by the tip of the grooves of the disk : posterior margin
very short, regularly rounded : base very obtusely rounded, in many
specimens a little contracted near the anterior termination : fosset
elongated, very distinct : within bluish-white ; perlaceous.

This large and handsomely sculptured shell, was found in the
Fox river of the Wabash, by Mr. Lesueur and Dr. Troost.

It resembles U. plicatus, nob., but on comparison it will be ob-

* Although. Mr. Lamarck quotes the proper name of this species as a
synonym, yet he has by some error changed it it to purperascens. That
it is an error is to be inferred from the observation under his description
of U. carinifera, where he says, " trSs-distinct de I'U. purpurea,''''

t [This is U. heros of N. H. Dis. ii, p. 291.— Ed.]

166

Lserved to differ very essentially from that common species. The
umbo and beaks of tlie jilicatus are very prominent and altogether
destitute of any small literations or divaricating lines, having only
the origin of one or two of the large undulations grooved upon it.
The primary teeth of the plicatus also are much thicker than those
of this species.

I formerly considered this species, with much doubt, as distinct
from the undulatus of Barnes, and gave to it the name of heros,
but notwithstanding some differences, I have concluded, after a
more mature examination and comparison, that it may be with
propriety referred to that species. Barnes drew his description
and figure from a specimen then unique, belonging to the cabinet
of Mr. S. B. Collins, which was so eroded as not to exhibit the
ornamental tubercles of the umbo and beak.

The dimensions of a fine specimen found by Mr. 0. Evans are,
length five inches, breadth over seven, and convexity two inches
and seven-tenths.

It is not iincommon in Fox river, an arm of the Wabash, in
muddy and sluggish parts of the stream. PL 16.

Unio abruptus. — Specific character. Subquadrate, truncate
before.

Desc. Shell oval-quadrate, yellowish olive or brownish, slightly
radiated with blackish-brown narrow lines, which do not extend to
the base : umbo not very prominent, rounded, slightly compressed,
generally radiated with obscure greenish, and placed far back,
almost terminal : disk convex, anteriorly with a hardly raised, very
obtuse elevation, becoming obvious towards the margin and a little
prominent at the anterior basal angle : hinge margin a little de-
pressed, so as to form an angle with the disk, more acute towards
the umbo : ligament higher than the beaks : anterior margin trun-
cated by an almost straight line : basal margin very slightly con-
tracted : posterior margin very short, gaping considerably from the
middle of the base to the cavity of the hinge membranes : cavity
of the hinge membranes very obvious, rather wide, as long or
longer behind the beaks than broad : within white, or tinged with
very fine fulvous-pink, or salmon color ; posterior cicatrix profound ;
smaller cicatrix rather large, oblique, arquated : palleal impression
hardly more prominent than the anterior cicatrix : cardinal teeth
thick, direct ; that of the left valve subtrifid : tooth plate rather

167

broad, projecting in a ledge on the inner side of tlie lamelliform
tooth of the left valve.

Var. a. Anteriorly more prominent and hardly truncate.

Ohs. The color of the inner surface is, in most specimens very
beautiful. The umbo is generally decorticated, exposing a surface
slightly tinged with the color of the cavity of the shell. The in-
ternal surface of this shell, as in several species, is minutely granu-
lated and undulated ; a character very sensible under the magnifier.

Some conchologists have considered this shell a mere variety of
the carwi^is, nob., probably because, like that species, it is generally
more or less truncated before ; but there are other characters
which appear to me to forbid a specific union. The ahruptus is
always of much less breadth, the beaks much nearer to the poste-
rior extremity, the perpendicular length from the beaks to the
base much greater ; the cardinal teeth direct, much more robust,
that of the left valve being trifid : whereas in cariosns the cardinal
teeth are slightly oblique, bifid in each valve, and the plate on
which the teeth rest is much more slender, even when the general
thickness of the shells is the same. It is more closely related to
U. ellipticus, Barnes, by the variety a ; but although the teeth
are nearly similar, yet that species is never truncated, the beaks
are never situated so far back ; the cavity of the hinge membranes
is much narrower ; the anterior division of the cardinal tooth of
the left valve is less obvious, and the ledge on the inner side of
the lamelliform [tooth of the same valve is but slight ; the aspect
or habit also is quite difi'erent. It occurs frequently in the Wa-
bash. PI. 17.

SoLECURTUS. — Shell equivalved, transversely elongated, gaping
at the extremities, which are obtusely and equally rounded ; hinge
and basal margins nearly parallel ; apex not prominent ; hinge dis-
tant from the extremity ; ligament external, short ; muscular im-
pressions two, remote, oval or angular, distinct ; impression of the
mantle profoundly sinuous before; teeth various, generally im-
perfect.

Oha. A genus formed by Blainville to receive ten or twelve
species, hitherto referred to the genus Solen, and to which they
are indeed very closely allied. He divides this genus into three
parts, viz:

A. Compressed, thin, with an anterior rib, obliquely decurrent

168

from the apex to the basal margin. >S'. radiatus, Linn. (Grenus
Siliqua, Megerle ; Leguminaria, Schum.)

B. More cylindric and destitute of the interior rib. S. strigiUa-
tus, Linn.

C. More elongated and subcylindric. >S'. legumevi, Linn.

These species shew the connection of the two genera to be inti-
mate ; but there is certainly a great difference in habit, which, in
conjunction with the notable characters of the rounded form of
the muscular impressions, the distance of the hinge from the ex-
tremity, &c., in the present group, seem to justify its separation
from Solen. Like the species of that genus, these reside in the
sand on the sea shores, secluded from observation.

SoLECURTUS COSTATTJS. — Specific character. Hinge nearly
equidistant from the posterior termination of the shell and the mid-
dle of the hinge margin. PI. 18.

Solen costatus, nobis. Journ. Acad. Nat. Sci. vol. 2, p. 315.

FuLGUR. — Shell pyriform ; spire very short ; varices none ', body
whorl very large ; aperture large, oval, extended towards the base
into an elongate conic,- open canal, which is entire at base ; um-
bilicus none ; epidermis deciduous ; labium concave with a single
fold or oblique groove near the origin of the canal and a slight
calcareous deposition above ; labrum simple : within having eleva-
ted striae which do not revolve far within the shell, nor do they
reach the edge of the labrum, but leave a smooth border ; opercu-
lum horny.

Ohs. This genus was formed by Montfort. Linn6 placed all
the species with which he was acquainted in his great genus Hfiirex.
Bruguieres, Lamarck and Blainville referred them to Pi/rula, a
genus with which they are certainly very closely allied, but from
which they differ in having a fold on the labium, in not being
vesicular and thin, in having elevated lines or stria3 within the
labrum, &c. Linn6 did not even perceive this alliance, if we may
judge from the fact that he placed these shells with Murex, as
above stated, whilst he referred the true Pt/rulx to his reservoir
Bulla. We do not know what difference exists between the ani-
mals. Naturalists do not appear to know whether or not they are
operculated, but we can affirm with certainty that the operculum
exists in the present genus. When recent the surface of the shell

169

is covered with a thin epidermis. It is always destitute of varices
and of umbilicus, and bears the same relation to Pyrula that Fas-
ciolaria does to Fastis. Indeed we would have more readily ac-
quiesced in referring them to Fasciolaria than to Pyrula,
although there exists but one fold on the columella, in place of

wo or three.
The excluded ovaries consist of a long series of oval, parallel

ollicles or disks of little thickness, attached by one side to a con-
necting string ; each of these disks contains numerous young ones,
of which the shell is very obvious and even tolerably firm in its
consistence. Such ovaries are very abundant on our coast. They
exhibit at length a rounded perforation in the edge of the follicle,
opposite to the string, whence the young shells escape. All this
this is very well represented by Lister in his Conchology, plates
879 and 881.

FuLGUR PYRULOIDES. — Specific cliaracter. Pale yellowish or
white, with rufous, dilated lines, interrupted in the middle ; suture
canaliculated.

Seha. Mus. vol d. pi QS,fig. 19, 20 ?

List. Conch., pi 877.

llartmi, Conch., 3, t. 661,/ 736, 737. {Lam.)

Encycl Meth., pi 443, /. 2, a, h. {Lam.)

BuUa ficus, var. b. Gmel

Fulgur pyruloides, nob. Journ. Acad. Nat. Sci., vol 2, p. 287.

Pyrula spirata, Lam. Anim. sans Vert., vol 7, p. 142.

Bulla py rum. Dillwyn, ed. Lister Conch., Index, p. 39.

Lamarck was unacquainted with the native country of his spi-
rata, the description of which he published in August, 1822,
which gives the priority to pyruloides, as this was published in
July of the same year, twelve months after it had been read to the
Academy. It inhabits our Southern coast, and I never found it so
far North as New Jersey. PI. 19.

[Am. Con., p. iii. Sept. 1831.]

Alasmodonta. — Shell unattached, transverse, equivalved, in-
equilateral ; cardinal teeth one in each valve, irregular, simple or
biparted ; lateral teeth none ; muscular impressions two principal

14

170

ones ; compound ligament exterior ; palleal line entire, uniting the
two muscular impressions.

Ohs. I formed this genus to receive several species of fluviatile
bivalves, which the characters of Unio and Anodonta exclude.
Lamarck placed some of the species in his genus Vnio, notwith-
standing his character of lateral teeth, " allongee, comprimee, se
prolongeant sous le corselet."

Blainville, in his " Manuel," has placed the genus as a subgenus
under Anodonta, with Iridina of Lamarck and Dipsas of Leach.

Cuvier in the first edition of his Regno Animal unites all the
genera of this family in Anodonta and Vnio ; and is still followed
in this arrrangement by some other naturalists, upon the principle
that inosculating species destroy genera. They appear to forget
that the same principle would reduce those two genera to a unit,
and would in fact eliminate a great portion of those groups, in all
departments of natural science.

Four different names have been applied by as many writers, to
designate this genus. Leach called it Damaris ; another name,
according to Swainson, was given by Dr. Turton ; and a third, that
of Margaritariaf^ by Mr. Schumacher. To all these generic names
the A. margaritifera of Linne was referred by their respective
authors, who do not appear to have been acquainted with either of
the several species which inhabit our waters.

Those who change the orthography of Anodonta to Anodon,
will write the name of this genus Alasmodon for the same reason.
One author writes it Alasmidonta and Blainville changes it to
Alasmisodonta, without abbreviation.

But those who assume the task of rejecting genera in this family,
in order to be consistent, must revert to the principles laid down
by Ferussac in his " Essai d'une methode Conchyliologique," pub-
lished in 1807. He reduces all the Naiads to the genus Unio,
and the remaining parts of his system, chiefly correspond with this
view of the subject. Mr. Sowerby, in the Zool. Journal, 1824, has
made the same proposition, though in his " Grenera " he retains

* Essai d'un nouveaux systeme des habitations des Vers Testacees,
1817. The priority of this date would lead me to adopt the name given
by that author, did it not appear that the work was not published for
several years after it was printed. It was not known to the naturalists
of this country, France, Germany or England until the year 1822.

171

Atlodontaf Iridina, and Hyria, as well as many genera in other
families, which the same principles of arrangement would abolish.
Ferussac, however, in his " Tableaux Syst.," 1822, has concluded
to admit four of the genera; viz. Anodonta, IJyria, Unio and
Castalia.

Alasmodonta confragosa. — Disks with short, oblique un-
dulations, and tuberculated beaks.

Alasmodonta confragosa^ nobis. Disseminator of Useful Know-
ledge, vol 2, p. 339.

Desc. Shell transversely suboval, very dark or blackish ; disk
convex, with oblique, irregular, abbreviated undulations, not di-
rected towards the beak ; and numerous, more or less abbreviated,
slightly elevated lines from the umbo, becoming obsolete towards
the base, those before divaricating towards the hinge margin ;
beak with a groove and double series of three or four tubercles •
lunule, or cavity of the hinge membranes somewhat arquated;
within white, margined with opake whitish, or violaceous.

Obs. This species was first obtained by Mr. 0. Evans in a side
stream of the Wabash, called Fox river ; several specimens have
been since obtained, but it is rather rare. The teeth resemble
A. rugosa, Barnes, but are much less prominent. On a passing
glance it might almost be mistaken for Unio pUcatus, nob.

The tuberculated beaks are somewhat like those of the figure 9,
plate 248, of the Encyclopedic Methodique, but that is represented
to have the lamelliform teeth. The largest individual I have seen
measures three inches and a half long, by five and six-tenths broad
and two and a half inches in convexity. In a particular, oblique,
reflected light, the surface exhibits a tinge of dark green.

I have recently received specimens from Mr. Barabino of New
Orleans, near which city he obtained them, and where they are
probably not uncommon. He did not state the precise locality,
but I presume they inhabit the sluggish waters in the rear of the
city, and not in the Mississippi. PI. 21.

Unio phaseolus, Hild. — Specificcharacter. Umbo compressed;
cardinal plate very thick ; lateral tooth short ; surface radiated ;
beaks simple.

Unio phaseolus, Hildreth. Journal of Science, vol. 14, p.
283. Short and Eaton, Transylvania Journ. of Medicine, for
February, 1831.

172

Unio cuneatuSj Var. Barnes. (^Note to Hildreth's essay.)
Unio planulatus, Lea. Trans. American Philos. Soc. N. aS'.,
vol. 3, pi. 9, ^. 13.

Desc. Shell transversely oblongovate, thick ; surface yellowish
.brown, with several rather broad radii, which are often interrupted,
by the larger lines of growth, into spots ; disks and umbo com-
pressed ; beaks simple or not undulated ; not elevated ; cavity of
the hinge membranes or lunule oval, acute ; ligament not elevated;
within white, somewhat grooved obtusely ; cardinal plate very
thick, with a considerable flattened space between the cardinal
and lateral teeth ; cardinal teeth rather small, direct ; lateral teeth
very short, oblique, and veiy thick ; anterior smaller muscular
impression immediately anterior to the tips of the lateral teeth.

Ohs. A striking similarity exists between this shell and the
cuneatus and gihhosus of Barnes, the latter of which, however, is
somewhat more slender, the cardinal teeth larger, the lateral teeth
longer, the beaks undulated.

In a note on Dr. Hildreth's description of phaseolus, Barnes
says it is a " white variety of cuneatus ;" and it must be confessed
that a considerable resemblance exists between some of their varie-
ties. But the latter species differs in the much less dilated car-
dinal plate ; in having the anterior smaller muscular impression,
situated immediately beneath the tip of the lamelliform teeth ; in
having the anterior lunule much more depressed, with slightly
elevated lines crossing the wrinkles.

The young of a corresponding age, accurately resembles, in its
outline, Barnes' figure of his mucronatus, but his description of
mucronatus agrees better with cuneatus than with any other species,
certainly much better than with gihhosus, inasmuch as it is stated
to be " purplish on the margin, and whitish in the centre," whereas
the latter is more commonly whitish on the margin than in the
centre, and the " anterior lunule long, distinct, with a marginal
furrow," of mucronatus, agrees with cuneatus, but not at all with
gihhosus.

This species is found in plenty in the Wabash, and is probably
also an inhabitant of most of the larger tributaries of the Ohio.

The branchial oviducts, when inflated with eggs, exhibit a series
of tubes, which, when dried, appear granulated under the micro-
scope ; these tubes are dirty yellowish, with a few blackish spots

173

near their tip ; beyond these spots is a yellow band, the tip itself
being bright sanguineous. PI. 22. The exterior, dorsal and in-
terior views of the shell, and the branchial oviducts.

Unio tetralasmus. — Spccijic character. Transversely elon-
siatcd ; lateral teeth two in each valve.

Desc. Shell transversely oblong-elliptic; rather thin, moder-
ately convex ; beaks but little elevated, decorticated ; hinge mar-
gin parallel to the basal margin, subrectilincar ; posterior margin
regularly rounded ; anterior slope with two impressed lines ; ante-
rior margin declining in an oblique rectilinear line from the ex-
tremity of the hinge margin to the subi'ostrated tip ; basal margin
subrectilincar; cavity of the hinge membranes (lunule) very slen-
der, obsolete ; umbonial slope not prominent ; within white, irides-
cent anteriorly and on the margin; numerous minute, slightly
impressed, longitudinal lines ; palleal impression not indented,
curved beyond the anterior muscular impression; anterior accessory
muscular impression very large, separate; cardinal teeth trans-
versely long, slender, very oblique ; lateral teeth distant from the
cardinal teeth, two in each valve, equally prominent in the two
valves.

Obs. For an opportunity to examine this species I am indebted
to Mr. Lesueur, who obtained it in Bayou St. John, near New
Orleans. It is readily distinguished from any other species. PL 23.

Unio dehiscens. — Specific character. Anteriorly biemargin-
ate; teeth obsolete.

Unio dehiscens, nobis. Disseminator of Useful Knowledge, vol.
2, p. 308.

Desc. Transversely much elongated, thin, rather compressed,
polished, pale yellowish green, or brownish, radiate with some-
what interrupted green lines, which are more or less dilated and
compound, and obsolete in the aged specimen ; anteriorly gaping,
and at the posterior inferior margin also gaping to the middle of
the base ; a slightly impressed line on the anterior hinge submar-
gin passes to the anterior margin, which is emarginate both above
and below the line, and subangulated at tip : posterior margin
rounded, extending considerably beyond the beaks : umbo and
beak not prominent, with slight undulations on the latter : primary
teeth consisting of a slightly elevated, very obtuse angle in the
right valve and obsolete sinus in the left for its reception : lateral

174

testh denoted by an impressed line; cavity of tlie umbo slight ^
but with a deep, obvious and large muscular impression immedi-
ately under the beak ; more or less tinged with purple.

Ohs. The anterior emarginations, above mentioned, are obvious
in many species, but are more particularly remarkable in the
present shell ; they mark the situations of the tubes of the animal.

The form and arrangement of the teeth are very much like
those of the monodonta, nob., but the outline and other characters
of this shell, as expressed in the above description and exhibited
in the plate, are widely different.

It is certainly an inosculating species between Unio and Ano-
donta, but traces of the primary and lamelliform teeth are, I be-
lieve, always discoverable. It is an inhabitant of the Wabash
river, and is not uncommon.

The largest individual that has occurred, is in length one inch
and three-tenths, and in breadth three inches and two-fifths ; but
the plate exhibits the usual magnitude. The cavity of the beaks
is often more or less tinted with purple. PI. 24.

SiGARETUS. — Shell ear shaped, univalve, spiral, depressed;
aperture very large, entire, embracing a portion of the preceding
volution, much wider than long ; destitute of nacre : columella
short, spiral : labrum simple : volutions two or three : muscular
impressions two, distant : operculum none : a revolving slightly
elevated line on the inner surface : spire lateral : periostraca none.

Ohs. These are marine shells, inhabiting various parts of the
globe. Like Ovtda, Oliva, &c., the shell is included within the
mantle of the animal. Of the few species yet discovered, Linne
considered one a Helix. Lamarck adopted the name of the genus
from Adanson, and placed it in his family of Macrostomes, with
SlomateUa , Stomafia and Haliotis, distinguishing it from the
others by being destitute of nacre. He says, it seems to have
j^oine relation to Natica ; and indeed some similarity is exhibited
by the S. concavus of that author, and an allied fossil species
which Mr. Hoeninghaus sent me under the name of caiialiculatua.
But as those shells are external, or not enveloped in the mantle
of the animal, the relation must be considered as of analogy rather
than of afiinity.

Cuvicr, who examined the structure of the animal of a specio
of this genus, but we are not informed which, either by name ot

175

description, says, it is so much like that of a Buccinum, that " to
make of the Sigaretus a, Buccinum, it is only necessary that the
whorls of the shell should be less unequal, and should be elongated
into a more acute spire." The animal as delineated in his plate,
or that part which is visible from above, consisting entirely of the
expanse of the thick, fleshy mantle, is oval and convex. On the
anterior margin, a little on the left, is a deep emargination, which
is the extremity of an open canal beneath, originating above the
neck in the branchial cavity, to which it conveys the water, and
in which are two pectinated and vascular lamelliform branchia>.
The shell is entirely enclosed in the convexity of the mantle. The
head is formed as in Buccinum. The tentacula are conic, with
the eyes at their base. The vent is posterior to the canal and
before the middle of the body. The foot much smaller than the
mantle and also oval. The sexes are in separate individuals.

Blainville has formed a new genus under the name of Grt/pios-
loma, for one or two East Indian species, the shells of which
though more depressed, are altogether generically similar to Sign-
retus, in which other naturalists place them ; but the animal,
agreeably to his description, differs in having a more elongated
form, appendiculated tentacula and but one large branchial pccten.

SiGARETUS PERSPECTivus. — Specific character. Depressed ;
beneath, revolutions visible almost to the summit.

Desc. Shell oval, very much depressed, but little convex, with
numerous, transverse, slightly undulated, sub-equidistant, impress-
ed lines and longitudinal wrinkles; transverse lines obsolete
beneath : spire not at all prominent, only a little convex : volutions
about three : sutui-e a simple impressed line : within, the slightly
elevated line is more or less obvious, not reaching the margin of
the labrum : revolution of the whorls visible almost to the summit.

Ohs. This shell is abundant on the coast of New Jersey and
farther south ; but I have never had an opportunity to examine the
animal.

I have carefully compared many specimens with a shell sent me
by Mr. Gr. B. Sowerby, under the name of haliotoideus, L., but
which seems more accurately to correspond with the leachii, Blain-
ville, as figured by Sowerby in his " Genera," and of which Blain-
ville has formed his genus Cryptostoma. So striking is the
resemblance that I have hesitated much to consider it a distinct
species.

176

The chief differences appear to be, that the present species has
more general convexity and the spire itself is slightly convex :
beneath, the breadth is less considerable between the outer mar-
gin and the edge of the mouth, and the revolutions of the spire
within are much more obvious. PI. 25, upper and lower figures.

SiGARETUS MACULATUS. — Specific character. Shell with two
maculated bands.

Desc. Shell oval, depressed, with very numerous, transverse,
hardly undulated, sub equidistant, impressed lines, and longitudinal
wrinkles ; the transverse lines are obsolete beneath ; two bands of
pale rufous spots, and a rufous band near the suture : spire hardly
prominent, slightly convex ; volutions about three ; suture a simple
impressed line : aperture very large.

Ohs. Although very much depressed, this pretty species is more
convex than the preceding, and the spire when viewed from the
side is more distinct ; the strise also are more close set. It differs
from all the species in having colored spotted bands, and within it
has a slight pearly appearance. This species is found on the
southern coast and is rare. PI. 25, middle figures.

Venus. — Shell equivalved, inequilateral, regular, closed, trans-
verse or suborbicular ; cardinal teeth three on each valve, approxi-
mate, anterior and posterior ones diverging from the summit; liga-
ment exterior; muscular impressions two, not elongated, remote,
connected by the submarginal impression, which is deeply sinuous
before.

Ohs. In this extensive genus are included some of the most
beautiful of bivalve shells. Linne referred to it species of the fol-
lowing genera : Petricola, Yenerupis, Sanguinolaria, Corbis,
Lucvna, Donax, Astarte, Oyrenay Cyprina, 3Ie</ades7na, Cytherea,
Venus and Venericardia. Although those species have been
since eliminated and more naturally distributed, yet in consequence
of the great accessions from the zeal of modern obsei-vers, and
owing to the considerable variation, both in sculpture and coloring,
that many of them undergo, great difficulty and uncertainty often
meet the conchologist in his endeavors to ascertain species, and
more than usual caution is requisite in detemining any one to be
new.

In general form and exterior appearance these shells are undis-
tinguishable from Cytherea, but the hinge of the latter has the

177

posterior cardinal tooth situated immediately under, and parallel to,
the edge of the lunule in the right valve, and a recipient cavity in
the left valve, similarly situated. Cyprina was separated, from the
circumstance of having an anterior, lateral, remote tooth. Vene-
nipia is very closely allied to Venus ; but the cardinal teeth are
parallel, and not divergent as in Venus ; they have the habit of
perforating and residing in limestone rocks. Sowerby has changed
the name of Venerupk and united to it several transverse species
of Venus, such as papilionacea, Itterata, &c., some of which, or
perhaps all, might enter Schumacher's genus Tapis. Several other
genera have been separated from the Linnajan Venus, such as
Calista and Arthemis of Poli ; Artliemis, Loripes and Meretrix of
Ocken ; Orbicuhis, Trigonia, Chione and Tapes of Megerle, and
others by Schumacher, but as we are unacquainted with the char-
acters of several of these we cannot estimate their relative value,
though we readily assent to the necessity of a reform in this
numerous and somewhat artificial group.

The animal of Venus has the foot rather large and compre ssed ;
the mantle is undulated and furnished with a series of cirri ; the
tubes are moderately long and united ; mouth small, semi-lunar ;
branchiae not united, broad and short. Lamarck described eighty-
eight recent species and six fossil ones, and Blainville states that
Defrance announces forty fossil species.

One of the most useful of our shells, the Clam, ( V. mercenaria,
Linn.,) belongs to this genus, but Schumacher has separated it
under the generic name of Mercenaria. It is the shell of which
our aborigines, with much persevering labor, formed their wam-
pum beads which they valued so highly, and which they strung
together in the form of belts and other ornaments.

Venus grata. — Specific character. Granulated with longitu-
dinal and transverse striae ; whitish, with dotted rays of pale fer-
ruginous and blackish ; blackish oblique lines before.

Desc. Shell transversely suboval, convex, with very numerous,
close set, longitudinal striae ; those on the anterior two-thirds of
the shell have a slight appearance of folds, or as if each one origi-
V nated beneath the one posterior to it in a somewhat imbricated
manner ; these striae are granulated by very numerous transverse
striae, which are more obvious on the posterior third of the shell,
and almost obsolete on the middle : color whitish, somewhat

178

tinged with green towards the umbones, broadly radiated with very
pale ferruginous and dusky purplish, with numerous dots and ab-
breviated lines of purple-black: anterior margin with transverse,
oblique, purple black lines : posterior margin pale ferruginous :
lunule dusky, bounded by an impressed line : umbones not very
prominent : hinge margin nearly rectilinear, terminated anteriorly
by an obtuse angle ; in this part the edge of the left valve laps a
little over and conceals the corresponding part of the edge of the
right valve : ligament deeply seated : posterior margin rounded :
lunule impressed, distinct by an impressed line : within, very
broadly margined with violaceous ; margin crenated : intermediate
tooth emarginated at tip : anterior tooth of the left valve also
emarginated.

Obs. This beautiful species was presented to me by the late Mr.
Stephen Elliott of Charleston, S. Carolina, as an inhabitant of the
west coast of Mexico. The colored lines on the anterior part of
the shell, are somewhat like those of V. geographica, Gmel., but
these lines have a bluish shade forwards, are more regular than in
the figure of that species in the Encycl. Meth., and as a species it
widely distinct.

I have an indistinct recollection of a figure resembling this spe-
cies, but I cannot recall the work, for the purpose of comparing
the characters. PI. 26.

ScALARiA. — Shell turrited; volutions convex, gradually in-
creasing in size to the aperture, with numerous, elevated, longitu-
dinal ribs or varices ; aperture nearly orbicular, slightly longer than
broad; peristome continuous, reflected; operculum horny, spiral,
thin.

Ohs. A genus of very pretty shells, known by the name of
Staircase shells by some collectors, and with respect to the nature
of which, naturalists formerly difiered much. Favanne and Gaul-
teri and others, believed them to be closely related to Serpula; and
Rumphius placed them in his Buccinwn. Such as were known to
Linne he referred to Turbo, on account of the rotundity of the
aperture. In this respect they certainly also resemble Cyclostoma
and Pupa ; but the elevated ribs distinguish them from the first,
and the successive and regular increase in the size of the volutions
separate them from such species of the latter, as have slight rib-
like elevations. They seem also to approach some species of the
genus Rissoa in the character of the ribs.

179

The largest and most beautiful species, the scalaris, L., (to
which Lamarck has siuce given a different name) was separated by
Leach as the type of a new genus, to which he gave the name of
Aciona ; it is the " Wentletrap or royal staircase shell" of the
English collectors, and Scalata of the French, belonging to the
subdivision of this genxis, which is distinguished by having the
volutions separated, or only touching each other by the projecting
ribs. This shell was very highly valued, and Leach mentions ;i
specimen '' which was purchased at a sale for twenty pounds ; but
it is now (1815) estimated as worth double that sum." Cubieres
says that in his time, a fine specimen of four French inches long
by three inches at base, was worth six thousand livres. To the
same division of the genus, it is said, about twelve species are re-
ferred.

Blainville, after Plancus and Muller, describes the animal to be
spiral, with a short oval foot inserted under the neck ; two tenta-
cula, with filiform termination, supporting the eyes at the extremity
of the inflated part ; a proboscis ? ; a long canal at the anterior right
margin of the respiratory cavity ; sexes separate.

They are all inhabitants of the sea. Lamarck has characterized
seven recent and five fossil species ; but Defrauce enumerates
twelve fossil species.

SCALARIA CLATHRUS, Lin. — Turbo clathrus, Linn. Gmel &c.

Scalaria communis, Lam,.

Scalaria clathrus, Auct. *

Desc. Variety c. Shell conic, turreted, imperforate, white, im-
maculate : whorls from six to eleven, touching each other only by
the ribs, but with a very narrow interval : ribs nine to each volu-
tion, prominent, simple, a little oblique, somewhat recurved and
with a more or less obvious, obtuse angle or shoulder above near
the suture : aperture oval-orbicular ; base a little angulated : labium
distinct.

Length from three-fifths to nearly nine-tenths of an inch.

Ohs. Inasmuch as the European specimens of clathrus in my
collection are almost all colored, spotted or banded and destitute
of any obvious angle or shoulder on the ribs near the suture, and
the suture is somewhat more contracted, I was led to describe
this as a distinct species under the name of angulata ; but as the
clathrus is often, and perhaps usually, destitute of color, and our

180

specimens frequently ocenr without mucli appearance of the angle
of the ribs, I have judged it prudent to place it as a variety of the
dathrus, though I propose that it be separated under the above
name. Lamarck describes a variety h, and although he quotes
the true Linnrean name of dathrus, yet he has placed the species
under a new name, which, agreeably to our principle relative to
the exclusive right of priority of description, we cannot admit,
notwithstanding the &ct that the word dathrus may apply equally
well to other species.

Our shell varies much in proportional diameter. The body
whorl, I believe, never becomes so large as in some specimens of the
European dathrus, neither does the whole shell ever become so
long as in other transatlantic specimens. PI. 27, two upper
figures.

SCALARIA MULTISTRIATA. — Specific character. Interstitial
spaces with very numerous, impressed, transverse lines.

Desc. Shell conic turreted, tapering to an actue apex, white,
Immaculate, imperforate : whorls about eight, in contact : costae
regular, simple, not reflected, equidistant, moderately elevated ;
spaces between the costse with very numerous, approximate, equi-
distant, impressed lines : suture well impressed : body whorl with
about sixteen cost».

Obs. Like the preceding, this is an inhabitant of the southern
coast, and is about half an inch in length. Mr. Elliott sent me a
specimen from Charleston, South Carolina, and obtained two on
the coast of Florida. It is readily distinguished from the preced-
ing species, by the very numerous small lineations that exist in the
spaces between the ribs, and at right angles with them. PI. 27;
lower right figure.

ScALARiA LINEATA. — Specific character. Costae on the body
whorl about eighteen : peristome very robust ; body whorl with a
raised line.

Scalaria lineata, noh. Journ. Acad. Nat. Sci. vol. 2, p. 242.

Obs. — This species is not uncommon on our southern coast. Its
length is about half an inch. A variety occurs, of which the
costae are almost obsolete, and another in which each rib, particu-
larly of the body-whorl, has an impressed line. The margin of
the mouth is greatly thicker than the ribs. What I have called

181

in the above description an elevated line, is, strictly speaking, the
line of junction with the basal surface which is a little more elevated
than the remaining surface of the volution, making a kind of step,
and not in reality a simple elevated line. In my observations on
this species, in the Journal above mentioned, I remarked that it
" very much resembles the clathratulus, Montagu, but the lip is
more robust and the basal portion of that part is more dilated."
PI. 27 ; lower left figure.

Amphidesma. — Shell rounded or transversely somewhat oval,
subineqiiilateral : hinge with one or two cardinal teeth, and having
a lateral tooth each side, sometimes obsolete ; a slender oblique
fosset originating immediately under the beak and passing an-
teriorly : ligament divided into two parts, of which the true liga-
ment is exterior and very short, and the cartilage portion is interior,
affixed in the oblique fosset : muscular impressions two, remote,
not elongated : parallel line with a much dilated and profound
sinus.

Ohs. — The characters of this genus are veiy distinct and easily
recognized from all those that have no part of the ligament inter-
nal. Lamarck first distinguished it by the name of jDonacilla,
which I think ought to be retained on the principle of priority,
and that of Amphidesma, that he afterwards applied to it, ought
to be rejected. He has associated it, in the same small group,
with JOngulina and Solemi/a, from both of which it may be known
by its much dilated and profound sinus of the palleal line. Other
genera of his family of Mactraceoe have divided ligaments, particu-
larly 3Iacfni, with which, in fact, Linne arranged the species; biit
their cardinal fosset is inore direct, dilated and deltoid, whilst that
of Amj)hidesma is nearly parallel with the edge, and fusiform. Lu-
traria is entirely destitute of lateral teeth, the valves gape and
the ligament is fixed in a deltoid cavity. Blainville unites Am-
phidesma with Lucina and with Fimbria, Megerle, or Corhis, Cuv.
But Corbis has lateral teeth, an exterior ligament, though deeply
seated 3 and the parallel line is entire, and the posterior muscular
impression is elongated.

Amphidesma transversum. — Specific character. Trans-
versely short oval; hinge nearly central.

Desc. — Shell transversely short oval, nearly equilateral, com-
pressed, a little gaping: anterior and posterior margins subequally

182

rounded, the latter somewhat more obtusely so : basal margin
regularly rounded, without any undulation before: apex obtuse,
but little prominent : cardinal teeth two : fosset dilated fusiform,
abruptly very narrow at the beaks : lateral teeth none : posterior
muscular impression very slender, and elongated.

This species is more transverse than usual in this genus ; it is
altogether destitute of lateral teeth, and the posterior muscular
impression is remarkably slender. It is superior in point of size to
either the orhiculatum or radiatum, nob., though proportionally
somewhat thinner. I obtained a specimen on the coast of Georgia
that is somewhat worn ; its color is whitish, a little tinged with
yellowish. PI. 28 ; middle figures.

Amphidesma ^quale. — Specific character. Left valve with
remote grooves instead of lateral teeth.

Amphidesma sequale, nobis. Jour. Acad. Nat. Sci., vol. 2, p.
307.

Obs. — This is allied to A. tenue and Boy sit, Montagu, of the coast
of England, of which, however, I have not any good description or
specimen to compare, and it may possibly prove to be the same with
one of these, when compaiison shall be made.

Since my quoted description was given, many specimens have
been found on the coast of Charleston, for which I am indebted to
the late Mr. Stephen Elliott.

It belongs to the genus Abra of Leach. PI. 28 ; four exterior
figures.

Fusus. — Shell imi valve, spiral, fusiform, canaliculated at base,
covered with an epidermis, and destitute of varices ; spire elevated ',
aperture oval ; columella simple ; labrum on" its edge simple ; oper-
culum horny, subconcentric.

Obs. — This genus was separated from the Linnsean Murex by
Bruguieres, who, however, included Pyrula, Fasciolaria, Fidgur,
and Pleurotoma, which have since been withdrawn from it by La-
marck and Montfort. The latter author distinguished another
genus by the name of Latirus, for the umbilicated species. Not-
withstanding these improvements, it is still acknowledged to be
an artificial assemblage, and more divisions must therefore be made.
Lamarck places the genus in his fjimily of Canalifires ; from all
the genera of which it is distinguished by very obvious characters,
excepting Pynda, which, however, consists of thin, more or less

183

canoellate shells, (I mean the true Jh/ruke,) with a very short spire,
aad pyriform, having the greatest diameter above the middle.
But as Buccinum, in another family, is at present constituted,
Ftmis is allied artificially even to that genus.

The species are numerous, and are marine. Lamarck enumer-
ates thirty-seven recent and thirty-six fossil species ; but wc are in-
formed that Defrance makes the number of fossil species amount
to sixty-six.

Fusus CORNEUS. — Specific character. Fusiform, unarmed,
transversely striated ; beak rather short, recurved.

Murex Cornells. Linn. Syst. Nat. p. 1224. Penant, Zool. vol.
4, p. 124, pi 76. Donovan, Nat. Hist. Brit. Shells, vol. 2,, pi. 38.
Moiit. Test. Brit. p. 158. {DiUwyn.)

Fusus islandicus. Martini Gonch. vol. 4, p. 159, pi. 141, (^Dill-
loyn.')

Murex islandicus. Gmel, Schrehers, (^Dillwyn^ &c. — Lister
Gonch.pl. ^1^, fig. 5

Desc. — Shell turrited-fusiform ; the greatest dilatation a little
below the middle ; unarmed : whorls about eight, convex, trans-
versely striated and longitudinally a little wrinkled : epidermis
pale brownish, deciduous : spire tapering, nearly as long as the
aperture and beak, terminating obtusely : labrum simple, smooth
within : columella naked, simple : beak of moderate length, slightly
arquated and a little recurved.

This is one of the several species of shells, which inhabit the
northern shores of America, in common with the coast of Europe,
and particularly that of Great Britain, as well as Iceland. The
late Mr. Z. Collins, a zealous and enlightened naturalist, presented
to me an individual which he found on the coast of New Jersey.
The color is whitish, but when living, it is covered with a brown-
ish deciduous epidermis.

Although the name icelandicus has been adopted by Lamarck
and other distinguished conchologists, yet with Pennant, Dillwyn
and others, I have retained the Linnaean name, for the all-
sufficient reason, that it has the priority ; whilst, at the same time,
it has the advantage of being preferable in itself, as the shell is
not limited to Iceland.

The resemblance between this shell and the antiquum, L., has
been noticed by many writers ; but that species is much larger,

184

more robust, the aperture more dilated, and the striae mueli more
crowded. Lamarck and others say that they may be distinguished
by the rectilinear beak of the antiqims. This also is a good char-
acter, but in my cabinet is a large and fine specimen of the latter,
of which the beak is as much recurved as in the present species.
PI. 29 ; upper and lower figures.

Fusus ciNEREUS. — Specific character. With elevated costae ;
and transverse, filiform lines.

Fusus cinereus, nob. Journ. Acad. Nat. Sci., vol. 2, p. 236.

Obs. — This species is common in the estuaries of the eastern
shores of Maryland and New Jersey. It has considerable resem-
blance to two figures in Lister's Hist. Conch, pi. 924, f. 16, b, and
pi. 939, f. 34, a. The first of which is considered an uncertain
figure, and the latter is said by Dillwyn to be the undatus, and is
interrogatively referred to by Lamarck. Our shell certainly ap-
proaches the genus Purpura in habit, but it cannot enter with
Lamarck's characters. PI. 29 ; two middle figures.

Paludina. — Obs. This genus may be distinguished from
Melania by the construction of the operculum, which has no other
than concentric lines of growth, whilst that of Melania has the
lines of accretion spirally radiate.

The name of the genus was adopted by Lamark from Bruguiere,
but Montfort applied to it the name of Viviparws, which is re-
tained by Blainville inhis plate, though in the text he adopts
that of Paludina.

Paludina ponderosa. — Specific character. Shell thick;
labrum more prominent towards the base.

Paludina ponderosa, nob. Journ. Acad. Nat. Sci. vol. 2, p.
173.

Obs. — This shell is common in many parts of the Ohio as well
as its tributaries. In its full grown state it is very thick and pon.
derous, enlarging so much in its body whorl, as to appear very
different from the young shell. In the early stages of growth it
resembles P. decisa, nob., from which indeed the back view would
hardly distinguish it ; but a sufficiently distinctive character re-
sides in the lower part of the labium, which in the decisa is not
obviously produced, whereas, in the present species it is consider-
ably advanced, as in many species of Melania, to which genus it
is closely related. PI. 30, fig. 1

185

Paludina subpurpurea. — Specific character. Penultimate
longer than the other volutions.

Paludina subpurpurea. Disseminator of Useful Knowledge,
vol. 2, p. 245.

Desc. Shell subglobular oval, not remarkably thickened ;'^ spire
longer than the aperture, entire at the tip : whorls five, slightly
wrinkled across, rounded but not very convex ; penultimate volu-
tion somewhat elongated : suture impressed : aperture ovate-
orbicular, less than half the length of the shell : labium with cal-
careous deposite : animal very pale bluish, with minute yellow
points, particularly on the rostrum, tentacula, and prominent
respiratory tube, which is as long as the tentacula : eyes on the
exterior side of the tentacula, near the middle of their length : the
anterior portion of the foot is very short.

Ohs. This species was first found by Mr. Lesueur and Dr.
Troost, in Fox river of the Wabash. In the young state the figure
is subglobose, and the aperture, although it hardly diifers in form
from that of the adult, is yet longer than the spire. They become
proportionally more elongated as they advance in age, and the form,
therefore, of the adult, is so diflferent from that of the young or
half grown, that in these states it may, very readily, be mistaken
for a widely distinct species.

The color of the shell is variable. In some it is pale horn,
more tinged with yellowish than with green ; in others are traces
of obsolete purplish bands, in many specimens the whole shell is?
reddish-purple, more or less obscure in different individuals.

In the autumn it is frequently found between the valves of dead
Unios, in which it enters perhaps to hybernate. The species i.«
certainly allied to the vivipara, but it cannot well be mistaken for
it, as it is much less dilated, the volutions less convex ; the penul-
timate volution is much longer in proportion to the length of the
body whorl, and the umbilicus is obsolete. Plate 30, f. 2.

Paludina intertexta. — Specific character. Shell with nu-
merous, minute, transverse, epidermal lines.

Paludina intertexta, nob. Disseminator of Useful Knowledge,
vol. 2, p. 244.

Obs. In good specimens two or three obsolete, pale bands are
visible by transmitted light. Plate 30, f 3, adult shell ; f, 4, old
specimen ; A, the operculum.

15

186

[Am. Con., p. iv., March, 1832.]

LiMNEUS. — Shell oblong, ovate, oval, conic or turrited, thin,
smooth ', spire prominent, more or less elongated ; aperture more
or less dilated, longitudinal, entire; columella at its superior part
or junction with the labium entering the aperture by a very ob-
lique fold or undulation ; labrum acutely edged ; operculum none.

" Animal oval, more or less spiral ; margin of the mantle thick-
ened on the neck j foot large, oval ; head with two triangular,
compressed, earshaped tentacula : eyes sessile, at the inner base of
the tentacula ; mouth with two lateral appendices, and armed with
a superior tooth ; orifice of the pulmonary cavity on the right, and
bordered by an appendage which can be folded in gutter ; orifice
of the reproductive organs distant ; that of the oviduct at the en-
trance of the pulmonary cavity ; that of the male organ under the
right tentacula." — (Blainville.)

Obs. A numerous genus of fresh water shells, inhabiting almost
every part of the globe. The species known to Linne were placed
in his great reservoir Melix ; in which he has been followed by
many of the English Conchologists, even of late years. Bru-
guieres, eminent for his useful reform in this science, separated it
from that genus, but did not distinguish it from his Bulhmis ; thus
uniting the differently organized animals of land and water in one
group. It is very true that some species of these two natural
genera resemble each other in the form of the shell, but they may
always be distinguished by the fold of the columella in the present
genus. Lamarck, aware that the animals were quite different in
organization, and that the one has two tentacula and the other
four, that one lives only in the water and the other altogether on
land, placed them in different families, and formed a separate genus
(as Muller and others had already done) under the above name,
which is now almost universally adopted for the present aquatic
group. The shell resembles Siiccinca, which, however, is destitute
of the fold of the columella, and its animal has four tentacula. But
of all the adopted genera, it is almost intimately related to Physa ;
and Sowerby, in his " Genera," has reunited the two groups. The
peculiar fold of the columella exists in both, but the animal of
Physa has the mantle remarkably dilated, so as to extend over

187

more or less of the exterior surface of the shell, and is digitated on
its margin, and the tentacula, which are short and compressed in
Limneus, are longer and almost filiform in the Phi/sse. The shell
also of the latter may be distinguished by being heterostrophe.
For these reasons we agree with Draparnaud and most modern
conchologists in separating Physa as a genus. It would seem also
proper to separate Aplexa of Fleming, the animal of which is des-
titute of a dilated mantle, though the shell itself resembles that
of Physa. Mixas of Leach may also, perhaps, be separated from
Limneus ; it was formed for the L. ghitinosus, Drap., which is a
fragile, vesicular shell, the spire hardly elevated, dextral, and the
mantle of the animal is reflected.

These shells are abundant in most of our lakes and ponds, as well
as in the rivers, east of the Alleghany Mountains. In our Western
streams they are less frequent, and even in some of them are of
rather rare occurrence. As the animal can only respire air un-
mixed with water, it is under the necessity of residing near the
surface or shore to obtain it. "Which, as its motions are slow, it
cannot do in rivers that are subject to very great, sudden and long
continued changes in depth, as is remarkably the case with our
Western streams. In order to take in a supply of air the respira-
tory orifice is opened at the surface with an audible snapping
sound, like that produced by the resilience of the nib of a pen.

Like the animals of some other shells it is capable of sustaining
itself at the surface of the water in a reversed position, the shell
being downward, and thus it can glide along to a considerable dis-
tance, by a slow movement. It does not appear to be capable of
rising from a depth to the surface voluntarily ; but it gradually
reverses its position from a supporting body that meets the surface,
or that approaches it within reaching distance.

Lamarck has described only twelve recent species, but many
more have been since made known and several fossil species have
also been described.

Limneus umbrosus. — Limneus elongatus, noh. Journ. Acad.
Nat. Scl, vol. 2, p. 167.

■Ohs. It inhabits in considerable numbers the ponds and tran-
quil waters of the Missouri, in the vicinity of Council Blufij and
Bigsby obtained specimens in Rainy lake and Seine river of Upper
Canada.

188

I am under the necessity of changing the name which I first
applied to this shell, that of elongatus being preoccupied by Dra-
parnaud for a very different species.

The fold of the columella is much less profound than that of L.
palustris, L., which it resembles. PL 31, fig. 1.

LiMNEUs RELEXTJS. — Limneus reflexus, nob. Journ. Acad.
Nat. Set., vol. 2, p. 168.
PI. 31, fig. 2.

Limneus elodes. — Limneus elodes, nob. Journ. Acad. Nat.
Scl, vol 2, p. 169.

Limneus palustris, L. ?

Obs. The fold of the columella is much more profound than
that of umbrosus. PI. 31, fig. 3.

Unio ventricosus, Barnes. — Specific character. Shell large,
thick, triangularly ovate, convex ; umbones large, round, promi-
nent : beaks recurved ; cavity capacious.

Unio ventricosus, Barnes. SilUman's Journal, vol. Q»,No. 2, p.
2Q7,pl l^,fig. 14, a, b,c.

Unio ovaius, var. b, Lam. Anim. Sans. Vertebr.,vol. 6, jo. 75.

Unio occidens ? Lea. Trans. Amer. Phihs. Soc, New Series,
rol. 3.

L>esc. " Shell with the anterior side very broad, subtruncate ;
posterior side rapidly narrowed, subangulated ; disks very convex ;
umbones large, round, elevated ; beaks recurved over the liga-
ment ; ligament large and prominent, passing under the beaks ;
anterior lunule depressed at the margin, fuscous, broad heart-
shaped, longitudinally waved ; hinge margin depressed between
the beaks; posterior slope carinate; epidermis yellowish-olive,
becoming chestnut-brown on the umbones ; rayed with green,
more conspicuous in young specimens ; in old ones the dark ehest.-
nut-brown covers the whole and conceals the rays ; surface smooth
and shining, reflecting the face of the observer ; young shells are
splendent, having a much stronger lustre on the outside than on
the inside ; cardinal teeth broad, prominent and obliquely flatten-
ed ; lateral teeth broad, elevated, and terminating abruptly before ;
cicatrices large ; cavity of the beaks unusually large ; naker pearly
white ; surface smooth, but not highly polished."

Obs. I quote the above description from Barnes' very useful
essay " On the genera Unio and Alasmodonta," in which this

189

species was first distinguished from the U. ovatus, nob., to which
it is very closely allied, and appears to be absolutely connected by
a gradual transition of intermediate varieties. The most striking
diiFerence seems to be the more depressed anterior slope of the
ovatus. Some old specimens and varieties are transversely more
elongated, as is represented in Barnes' figure c. The color also is
more or less yellow, radiated with green, or tinged with reddish
brown, particularly on the umbo, and sometimes extending over
the whole surface, almost obliterating the rays. On the inner an-
terior side, some specimens are beautifully tinted with a pink color,
but this is not very common ; they are generally white. It is very
common in our western waters. The U. occidens of Lea may
perhaps be U. ventricoms, var. h, Barnes. PI. 32.

Unio interruptus. — Specific character. An elevated um-
bonial slope, separating folds of the disk from folds of the anterior
margin.

Unio interruptus, nob. Transylvania Journal, vol. 4, p. 525.

Desc. Shell transversely oblong oval or subrhomboidal, black-
ish brown ; an elevated rib extends from the apex to the anterior
basal angle along the umbonial slope; anterior half of the disk
with somewhat oblique undulations extending nearly to the um-
bonial rib \ anterior to the umbonial rib are several arquated un-
dulations, which do not reach the edge of the shell, and are cut
by an impressed line which is nearly parallel to the rib ; umbo
compressed ; beaks not elevated, deeply eroded ; posterior margin
very short, rounded; ligament margin rectilinear, the anterior
angle elevated, obtuse ; anterior slope very oblique ; base recti-
linear, parallel to the ligament margin ; anterior basal angle some-
what rostrated ; cavity of the hinge membranes (or excavated
lunule) fusiform; within purplish, iridescent; cardinal teeth direct,
deeply granulated and lineated over their whole surface ; lateral
teeth entire ; posterior cicatrices rough, the smaller one orbicular ;
anterior edge blackish.

Ohs. The species to which this makes the nearest approach, is
undoubtedly the undulatus, Barnes ; but it is more transverse, more
oblique anteriorly ; the edges of the hinge margin and of the an-
terior slope are undulated, the umbonial slope is elevated into u
distinct separating rib ; and it is of a fine livid purple color within.
The eroded surface of the umbones is pcrlaceous, iridescent, and
at the apices it exhibits a dull waxen yellow surface.

190

For this interesting species I am indebted to Mr. Joseph Bara-
bino of New Orleans, who informs me that it inhabits Bayou Teche,
in the parish of St. Mary, Louisiana. PI. 33.

Unio glebulus. — Specific character. Oval orbicular ; lateral
teeth remote, very short, granulated.

U. glebulus, nob. Transylvania Journal, vol. 4, j9. 526.

Desc. Shell transversely oval orbicular, sometimes subovate, very
convex, dark brownish : umbones not elevated above the general
curvature : beaks not prominent, (much eroded, exposing a wax
yellow surface :) hinge and basal margins correspondingly arquated ;
destitute of any prominent angle : anterior and posterior margins
almost equally arquated ; the former extending a little with age
into a more or less obtuse angle at the extremity of the umbonial
slope : umbonial slope slightly elevated : lunule not dilated : within
a little tinted with rosaceous : cardinal teeth deeply and approxi-
mately granulated and sulcated : lateral teeth remote from the car-
dinal teeth, remarkably granulated; length hardly greater than
their distance from the cardinal teeth : posterior accessory cicatrix
small and approximate.

Ohs. The transverse simple rotundity of this shell, combined
with the much sulcated cardinal teeth and the remote, short lateral
teeth, readily distinguish it. Several specimens were sent to me
by Mr. Barabino, as inhabiting the same locality with the preced-
ing. PI. 34.

Unio declivis. — Specific character. Anterior margin recti-
linearly and obliquely truncate.

Unio declivis, nob. Transylvania Journal, vol. 4, j?. 527.

Desc. Shell transverse, moderately thick ; posterior margin short
and obtusely rounded : beaks hardly elevated : hinge margin rather
elevated and compressed, angulated at tip : anterior margin recti-
linear, descending obliquely forward, to a prominent rostrum of
the anterior basal margin at the extremity of the umbonial slope :
umbonial slope not elevated above the curvature of the disk, but
is bounded on its anterior side by two slightly impressed lines :
basal margin arquated : surface deeply wrinkled : within tinged
with purplish : cardinal teeth oblique : lateral teeth distant from
the cardinal teeth, rectilinear, oblique with respect to the base.

Obs. Several specimens were sent to me by Mr. Barabino, who
informs me that they were found with the preceding by his friend
Mr. Jauin in the Bayou Teche.

191

It resembles ^Mr/)MreMS, nob., but in that species tbe cardinal
teeth are direct, and a remarkable feature is exhibited by this
shell in its anterior rectilinear declivity, terminating below the
anterior middle in a kind of rostrum or prominent angle, which
may be compared to that of nasutiis, N., excepting that it is nearly
on a line with the base. I have not seen any variety of either of
those species that could be mistaken for this. The beaks and um-
bones in my specimens are very much eroded, exposing a wax
colored surface. PI. 35.

Arca. — Shell transverse, more or less elongated, and oblique ;
anteriorly subrhomboidal, inequilateral, subequivalve j summits re-
mote ; hinge rectilinear or slightly curved and furnished with a
series of numerous, vertical inserting teeth, which decrease in size
from the extremities to the centre ) two muscular impressions, re-
mote, connected by a simple parallel line ; ligament broad, extend-
ing both before and behind the summits, and expanding over the
rhomboidal surface beneath the summits ; animal with a byssus.

Obs. Linne included in his genus Arca, not only the species
of which it is at present constituted, but those also which have
been since distinguished by the names of Pectunculus and Nucula.
Gmelin added to it his A. cucuUus, afterwards separated by La-
marck under the generic name of CucuUoea.

As respects Niccula it appears that the relation to Arca is rather
one of analogy than of affinity, and it is possible that Turton may
be right in separating it entirely from the Arcaccx, with which
its numerous teeth bear some resemblance ; but the propriety of
placing it in the family of Mactra^ese, only by the character of the
internal ligament, seems to be questionable.

CucuUoea corresponds with the present genus in its general ap-
pearance, and we know of no other difference than that exhibited
by the teeth, which are less regular, and those at each extremity
of the series are transversely elongated.

Pectunculus is a closely related genus, differing chiefly by the
arquated series of teeth ; the general orbicular form, and by the
valves closing completely so as to prevent the passage of a byssus.

Ferussac in his Tabl. Syst., places Trigonia in this family ; but
the teeth are dissimilar, and the animal is unknown.

The Arcse, are marine shells, and, as Lamarck observes, some of
the species have one of the valves extending beyond the other on

192

the basal edge. Some are covered by a kind of hairy epidermis.
Blainville says, that the animal has the body thick, of a somewhat
variable form; abdomen provided with a pedunculated, compressed
foot longitudinally divided ; mantle with a simple range of cirri,
and a little elongated before ; the tentacula are very small and
very slender.

[Arca staminea, pi. 36, fig. 2, and Aeca lienosa, pi. 36, fig. 1, being
fossil species, I have omitted the descriptions. — Ed.]

SiPHONARiA. — Shell oval or subovate, patelliform ; apex nearer
one side and one end, curved in a direction opposite to an angle
on the basal edge ; within, an indentation dividing the muscular
impression and extending to the angle of the lateral edge.

Ohs. Adanson was the first to detect the differences between a
species of this genus, the S. mourefus, Bl., and Patella which it
resembles in general form. He was succeeded by Blainville, but
it is to Sowerby that we are indebted for the genus and name
which are now adopted. Gray formed a genus for the Gadin of
Adanson, which, however, is referred by other authors to the present
group ; Adanson did not describe its animal ; but it is evident
from his figure that the two sides of the shell are not symmetrical.

It resembles Patella, but the shell is distinguished by an un-
symmetrical angle on one side, (sometimes obsolete,) denoting the
position beneath of the termination of a syphon or respiratory organ
of the animal of which the trace remains. On the outer surface,
corresponding with this mark, is generally an elevation or rib, ex-
tending from the summit to the edge, but it is sometimes obsolete.

Blainville gives the following characters of the animal : body
oval subdepressed ; head subdivided in two equal lobes ; tentacula
and eyes indistinct ; margin of the mantle crenulated and extend-
ing beyond a suborbicular foot as in the Pafellas, branchial cavity
transverse, open a little before the middle of the right side and
provided in that part with a fleshy lobe, of a square form, situated
in the sinus between the mantle and the foot ; retractor muscle of
the foot, divided into two parts, of which the posterior is much the
larger, arquated ; the other very small, before the branchial orifice.

Several species are known, attaching themselves to rocks and
other fixed bodies. _

SiPHONARiA ALTERNATA. — Patella altemata, nob. Jour.
Acad. Nat. Sc. vol. 5, p. 215.

193

Obs. This is a small species, and the slight irregularity in the
curvature of the lateral edge, exhibits the unequivocal characters
of this genus. PI. 38.

BuLLiNA. — Shell cylindrical-oval, convolute, imperforate ; spire
elevated, short; aperture longitudinal, elongated, much narrowed
above; labrum simple, gradually much more prominent in the
middle than at the extremities, meeting the preceding volution
with a deeply re-entering angle ; at base widely and regularly
rounded ; columella with a slight fold.

Obs. Blainville quotes Ferussac for this genus, which, perhaps
inadvertently, he calls Bulme, with one 1, instead ofBullinaas the
latter author writes the word. He has, however, considerably
limited the group by assigning to it the character of " fortement
involv^es, spire visible et saillante a I'exterieur ; I'overture tres
etroite en arriere," which excludes some of the species compre-
hended by Ferussac. He also places it as a subgenus under Bulla,
with " la Bulle, la Jonkaire," of Basterot, as its type. The ani-
mal differs from those of the genera Bulla, Scaphander and At^/s,
by having two distinct tentacula, and from Bullea by being in-
cluded within the shell. The shell differs by its prominent spire,
which in those genera, when it exists at all, is umbilicated.

In its general form and habit it has much resemblance to Vol-
mirta, ; but the shells of that genus are emarginate at base.

BuLLiNA CANALICULATA. — Volvaria canaliculata, nob. Jour.
Acad. Nat. Sc. vol. 6, p.. 211.

Obs. This genus has been constructed subsequently to the pub-
lication of my description of the above species.

In comparison with a fossil shell of Dax, sent to me by Mr.
Hoeninghaus of Crefeld under the name of B. lajonkeiriana,
Baster., before mentioned, it is a little larger, and evidently dif-
ferent in having the shoulder grooved ; whereas in that species the
.shoulder is acute and the suture is profoundly impressed. PI. 39.

Gardita. — Shell equivalved, inequilateral, thick, suborbicular,
free, regular, ribbed, the margin crenate ; epidermis distinct ; hinge
of two teeth, one of which is short, direct, and the other oblique,
elongated in one valve, and in the other valve, is a large cardinal
recipient cavity with an oblique tooth on each side of it, nearly
parallel with the margin ; ligament subexterior ; two obvious mus-
cular impressions united by an arquated, entire palleal line.

194

Ohs. Poll informs us, that the animal resembles that of Ano-
donta and Unio ; and accordingly Blainville places the genus next
to that group with Venericardia and Cypricavdia as subgenera ;
botb of which Lamarck had separated from Brugui^re's genus
Cardita.

Venericardia is much like the present genus, with which Sow-
erby unites it, and is chiefly distinguished by the teeth being all
oblique and directed towards one side. Cypricardia is also very
similar ; it is remarkably inequilateral and has three teeth in each
valve. Many of the species of Cardita resemble Cardium on their
exterior surface, but the insulated lateral teeth of the latter are an
obvious distinction. The three genera are certainly very closely
allied in nature.

Some changes will undoubtedly be required in this genus. It
is not now to be admitted that the G. concamerata, Brug., can re-
main in the same genus with the species represented in our plate.
Particularly as the remarkable chamber which exists in that shell
seems to be devoted to a purpose altogether peculiar. On this
subject the late ingenious Miller wrote me as follows : '' You have
probably seen an account of the interesting discovery of the use
of the conic chamber or pouch in Chama concamerata ; almost
immediately after the statement was published, I received speci-
mens from the Cape, that not only shew the eggs, but also minute
shells, in the pouch."

Some slight approach towards a similar form may be found in
the Jeson of Adanson and in the C. rufescens, Lam., and perhaps
even in the C. calycidata, L., and C. crassa, Lam., which are included
in the subgenus that Blainville named Mi/tilicardia ; though it is
hardly probable that they can enter into the same group with the
concamerata.

Lamarck has described twenty-five species, of which three are
fossil.

Cardita tridentata. — Venericardia tridentata, nob. Jour.
Acad. Nat. Sci. vol. 6, p. 216.

Obs. The large recipient cavity of the hinge of the right valve
is somewhat similar, though wider in proportion, to that of the
corresponding valve of Cypricardia modiolaris, a very entire
specimen of which was sent to me by Mr. Hoeninghaus. Plate 4(>.

195

[On page 4 of cover of Am. Con. p. iv.]

Notice. — In the last No. I remarked that the Alasmodonta confragosa,
nob., was found by Mr. Barabino near the city of New Orleans ; this is
an error altogether my own, and which I thunk that gentleman for ena-
bling me to correct. He obtained his specimens from Bayou Teche in
the Parish of St. Mary, Louisiana, about two hundred miles N. N. W.
from New Orleans. I did not suppose they were found in the Mississip-
pi, and my interesting correspondent says, ' ' I have not yet discovered
any bivalves in the Mississippi, (near New Orleans), although I have
tried two summers successively, with an instrument made for that pur-
pose."

The Ampularia urceus, L. {rugosa, Lam.) is stated in the books to in-
habit the Mississippi river ; but I have never been so fortunate as to find
it, or to gain any information relative to it there. Mr. 0. Evans did me
the favor to make enquiry at various places on that river, and to exhibit,
as somewhat similar, a colored plate of the A. globosa, Swains., to per-
sons from whom information might be expected, and amongst others to
some Indians, who in general are known to be accurate observers ; but
no one has seen any similar shell in the waters of the Mississippi. I am
therefore much inclined to believe that the species is a native of some
of the more southern rivers, probably those of Texas. Any informa-
tion in relation to it, or specimens of the shell, will be very acceptable.

[Am. Con., p. v. Aug. 1832.]

Unio lapillus. — Specific character. Very small, thick, radi-
ated ; teetli very thick.

U. lapillus, nob. Transylvania Journal of Medicine. Vol. 4,
p. 528. .

Desc. Shell transversely suboval, thick, obscure yellowish, with
very numerous dark green radiating lines : posterior margin not
very short, rounded : beaks but little elevated, simple : lunule
fusiform, very obvious : hinge margin and anterior margin a little
depressed, declining gradually in an arquated line : anterior basal
margin rounded : basal margin nearly rectilinear in the middle :
within pearly white ; cardinal teeth direct, thick ; lateral teeth
thick, oblique with respect to the base : cicatrices very deep and
rounded : cavity of the beaks almost obliterated, with a series of
small cicatrices, extending downwards and backwards.

Ohs. The robust teeth and the thickness of the whole shell.

196

liave induced many, and myself amongst the number, to consider
this shell as the young of gihhosus, Barnes ; but a very slight ex-
amination serves to show that it is very distinct. The young of
that species is always much more elongated transversely, not so
thick, with the beaks much undulated, and the series of small
cicatrices in the cavity of the beaks is jjarallel to the hinge mar-
gin. As respects magnitude it approaches parvus, Barnes, which,
however, has the beaks undulated, is rather thin, with oblique,
small, cardinal teeth. Plate 41.

Unio CAMPTODON. — Specific character. Beaks distinct from
the posterior margin ; lamelliform teeth arquated at tip.

Desc. Shell moderately thin, transversely oblong-oval, a little
compressed, dark brownish, or blackish ; beaks with regular small
undulations, behind the middle but remote from the posterior edge,
but little prominent; ligament slope somewhat compressed, with
two distinct compressed lines ; umbonial slope not elevated above
the level of the disk ; anterior margin a little prominent towards
the base and rounded ; lunule large ; posterior margin prominent,
extending far behind the beaks and rounded ; base a little con-
tracted in the middle ; within milk white ; teeth, a single rather
long, oblique, undivided primary tooth in each valve ; lateral teeth
rather slender, towards the tip a little arquated.

Ohs. This interesting, new shell was sent to me by Mr. Bara-
bino, who discovered it opposite to New Orleans in ponds. An
exterior view of the shell would not immediately distinguish it
from Alasmodonta edentula, nob., but the inner surface is quite
different, and the armature of teeth separates them generically.
PI. 42.

Unio lugubris. — Desc. Shell transversely subovate, inflated,
dark brownish, wrinkled ; umbones prominent ; beaks not ver}-
prominent, eroded ; ligament margin slightly arquated ; ligament
more or less concealed ; anterior margin very widely rounded,
sometimes truncate or even subemarginate ; posterior margin rather
prominent, but very short ; base often a little contracted in the
middle ; within pale lilac ; cardinal teeth oblique, compressed,
denticulated ; lamelliform teeth slightly arquated, granulated and
striated at tip ; posterior accessory cicatrix rounded, rather deep ;
anterior margin somewhat iridescent.

197

Unio ater, Lea. Trans. Am. Phil. Soc, vol. 3, pi. 7, New iSeries.

Obs. I received several specimens of this shell from Mr. Bara-
bino, who obtained them from Bayou Teche, Parish of St. Mary,
Louisiana. It seem to be intermediate, and almost connected by
means of varieties, to U. cariosus, nob., and ventricosus, Barnes ;
like those species it has the posterior side prominent and very
short, the anterior margin often truncate and the primaiy teeth
often double in both valves ; but, however close this alliance may
be, it can be distinguished by its somewhat different habit. It is
differently colored, less cylindrical than cariosus, and proportion-
ally longer and more cylindrical than ventricosus.

In the young state the ligament margin appears to be coalite,
and that of the older shell retains this union on its anterior portion .

The name afcr is preoccupied by Nilsson for a very distinct
species. PI. 43.

Crepidula. — Shell free, univalve, irregular, ovate or oblong,
convex, somewhat patelliform, with an epidermis ; spire very short
or obsolete, apex obvious, obliquely inclined, towards the margin :
within horizontally divided about half the length by a diaphragm ;
muscular impression lunate.

Animal more or less depressed, oval, curved in the posterior
part ; mantle very thin, without marginal tentacula ; foot not
thick, small and rounded ; body each side of the head auriculated ;
head emarginate before ; tentacula two, subcylindric, or subconic,
slightly contractile, with the eyes near their exterior base ; mouth
in the emargination, without teeth; branchial cavity very large,
situated on the anterior part of the back, containing a fascicle of
long branchial filaments, which extend forward, and at tip float on
the right side of the neck ; anus on the right side.

Obs. These are marine shells attaching themselves to various
objects. At least many of the species have no locomotion, passing
their whole life in one spot, and being moulded upon the surface
of their resting place, exhibit its curvature and inequalities.

Lamarck separated the species from the Linneau Patellse, form-
ing a very natural and very distinct group. For although it ex-
hibits a slight similarity to Septaria, Feruss., yet it is readily
distinguished from that shell, which has not a proper diaphragm,
the labium being only a little prominent and acute ; it is also a
fresh water, operculated shell, allied to Neritina.

198

The genus Pileohis, Sowerby, has a very prominent labinm or
diaphragm, but the spire is altogether concealed.

Crepidula plana. — Crepidula plana, nob. Journ. Acad.
JYat. Sci.,vol 2, p. 226.

Obs. This species is remarkable for its depression, being with-
out convexity above, and is even often curved upward. In order
to give space beneath for the substance of the animal, the margin
of the shell is vertically deflected. The general curvature is various
in different individuals, being modified in compliance with that of
the surface on which they rest. PI. 44.

MoDiOLA. — Shell equivalve, inequilateral, obliquely elongated,
more or less subovate, regular ; summits near the posterior ex-
tremity, but not terminal ; anterior margin obtusely rounded ; pos-
terior margin short, rounded ; posterior base a little gaping to
permit the passage of the byssus ; ligament marginal, rectilinear,
subinterior, elongated ; hinge edentulous ; two principal, remote
muscular impressions, of which the anterior one is larger, and secu-
riform ; palleal impressions entire.

Obs. A genus of marine bivalves, separated by Lamarck from
the Linnasan genus Mytillus, in consequence of the beaks not be-
ing terminal, as they are in that group. It must be confessed,
however, that they are very closely related, con-esponding in the
other characters of the shell, as well as in the habits of the animal,
the organization of which, according to the anatomist Poll is simi-
lar, and to which collectively he appropriates the name of Calli-
triclie ; for a description of it the reader is referred to the genus
Mytillus. Several species blended by Lamarck in Modiola, were
separated by Cuvicr under the name of Lithodomus, in conse-
quence of their habit of penetrating and dwelling in the interior of
calcareous rocks and other solid substances ; their shell, excepting
its more cylindrical form, has much the character of 3Iodiola ; but
it is probable, judging by their mode of life, that the characters of
the animal will justify the arrangement of Cuvier.

The byssus is a fascicle of filiform fibres, each of which is sud-
denly enlarged at tip so as to form a little disk, that is applied by
the foot of the animal to the supporting object.

Lamarck described twenty-three recent and several fossil
species.

199

MODIOLA PAPUANA. — Specific character. Shell oblong, epi-
dermis reddish-brown, shell violaceous.

Musculus papuanus, D'Argenv. Conch. (^Lam.)

Modiola jjapuaim, Lam. An. sans Vert., &c.

Desc. Shell oblong, subovate, very narrow behind and widely
rounded before ; umbonial slope obtusely rounded and prominent ;
surface rather deeply wrinkled ; epidermis reddish-brown, beneath
which the surface of the shell is more or less violaceous ) within
dull whitish, somewhat iridescent.

I received several fine specimens of this shell from Dr. D. H.
Storer as inhabiting Cape Elizabeth and Front's Neck, Maine. It
is the common " Horse muscle " of the English collectors and ap-
pears to be abundant in the European Ocean and Mediterranean
Sea. Leach says, " beneath the epidermis the shell is invariably
whitish," whilst Lamarck says, '' Epiderme noiratre ; test lilas."
The shell appears to become more elongated with age.

Adanson's figure (pi. 15, fig. 1,) generally quoted for this species,
is probably altogether distinct ; it is but little more widely rounded
anteriorly than posteriorly, and the dorsal angle is much more
prominent. Leach quotes Mytilhis modiolus, Linn., as a synonym
of M. papuana ; but Lamarck and some other conchologists quote
it with doubt as the same as Modiola tvlipa. Lam.

Laskey, in the Transact, of the Wem. Soc, says they attain to
the length of nine inches ; the largest in my collection is five
inches and three-fourths long. PI. 45.

Melania virginica. Var. a. Shell destitute of the rufous
bands. PI. 47, f. 2.

Buccinum virginicum, Gmel. p. 3205, Dillw. Descr. Catal.
p. 652.

Lister, JSi/nop. pi. IIS, fig. 7.

Paludina virginica, nob. Nicholson's Encycl. (3c? Am. Ed.")
art. Conch, pi. 2, fig. 4.

Melania fasciata, MenJce, Synop. Mollusc, p. 82. [Var. a.]
Lister, Synop, pi. 110, fig. 4.

Melania multilineata, nob. Jov,rn. Acad. Nat. Sci., vol.
b,p. 380.

Melania curta, Menke, Synop. Mollusc, p. 81.

It is closely related to M. virginica, nob., but may be distin-
guished by its striae. PI. 47, fig. 3.

200

Melania semicarinatAj nob. Disseminator of Useful Know-
ledge, vol. 3. PI. 47, f. 4.

Melania laqueata, nob. Disseminator of Useful Knov-
ledge, vol. 3. PI. 47, f. 1.

Ranella. — Shell oval or oblong, more or less depressed in con-
sequence of having a range of varices only on each side, forming
a somewhat oblique longitudinal series ; aperture oval, the labium
being much arquated ; base canaliculated, sometimes a little emar-
ginated ; a sinus at the superior termination of the labrum ; epider-
mis distinct ; operculum horny ?

Obs. These are the Frog and Toad shells of collectors, a genus
of well marked Marine shells dismembered by Lamarck from the
Linnean Murex, in consequence of their lateral margined character.
Montfort made another division of these shells ; to those with an
umbilicated columella he gave the generic name of Apollon, and
those which have no appearance of umbilicus he named Biiffo ;
these designations, or rather their corresponding words Appole and
Crapaud, are adopted by Blainville as subgenera of Ranella.
These shells are sufl&ciently distinct from those of any other group
and cannot be mistaken, if we except a few species which approach
Triton, (a name which ought to be changed, as it had been pre-
viously applied as a scientific designation by Laurenti to a genus
oi Amj)hibia) a genus which is distinguished by having its varices
rare and not at the equal distances of half volutions from each
other. The animal does not seem to be known, but judging by
analogy, it probably resembles that of Triton and Murex and ha?
therefore a horny operculum, composed of lamelliform elements,
disposed in an imbricated manner, and commencing at the superior
tip. It must also be carnivorous.

Ranella caudata, nob. Jour. Acad. Nat. Sc. vol. , p. 236.

Obs. This is a common species on the coast of the United
States. Its generic affinity is not always obvious, as in some
specimens the varix of the aperture, only, is well formed. PI. 48.

Ceritiiium. — Shell more or less turritcd, often tubercular; aper-
ture small, oblique, with a short, truncated or recurved canal at
base which is not emarginated ; labium concave, more or less dis-
tinct, groove at the junction of the labrum with the preceding-
whorl J operculum small rounded.

Animal much elongated ; mantle prolonged in a canal on the left

201

side ; foot short, oval, with an anterior marginal groove ; head with
a proboscis, depressed ; tentacula remote, with the eyes on their
middle, beyond which they are slender ; mouth terminal, vertical,
without labial tooth and with a very small tongue ; a long and nar-
row branchia.

Ohs. Brugui^ire adopted the name of this genus from Adanson,
who says, that Fabius Columna used the word to designate one of
the species. The following is the descriptive appellation of the
latter, " Buceinum tuberosum Cerithium parvum." • All the species
which Adanson referred to it are correctly placed, with the ex-
ception of the Ligar, {Turritella tcrchra, L.) and the Mesal, botli
of which he was aware diJBFer generically from the others. He thu;^
describes the operculum of C. radula, L., and his figure corres-
ponds in character, " opercule exactement orbiculaire, cartila-
gineux, fort mince, brun transparent et marqu6 de cinq sillons^
circulaires concentriques," but Blainville says it is subspiral.
They are marine, and crawl upon the mud, feeding upon small
animals.

These shells are generally elongated cones, beautifully decorated
with regular series and bands of granules, tubercles and other sym-
metrical protuberances. Linne placed the species known to him
in the very different genera Murex, Trochus and Stromhus. Blain-
ville includes, as subgenera, Pyrena, Lam., Potamides, Brong..
Pyrazas, Montf, Nerine, Def, and Triphora, Desh. The aper-
ture of the two latter have a complicated appearance, and the
others are altogether destitute of canal.

Numerous recent and still more fossil species have been described,
chiefly by Lamarck, who remarks, that the more our collection.';
become enriched, the more difficulty attends the determination of
of genera, and particularly of species ; the vacancies which we sup-
posed to be natural limits become proportionally filled up. The
difficulty he experienced in fixing the character of each species
of Cerithium led him to the conclusion, that it is principally
in this genus that this fact is the most evidently shown, because
the collections abound in these shells. The study of these shells is
very important to the geologist in his attempts to ascei'tain the
changes that have taken place in the surface of the globe.

Cerithium muscarum. — Specific diaracter. White, with
costae, transverse stride and series of brown spots.

16

202

Desc. Shell oblong-conical, with rather distant, longitudinal,
prominent ribs, and distant prominent spiral striae, ■which by pas-
sing over the ribs give the latter a crenate appearance, and are five
in number on the body whorl and four on the second, the intervals
with smaller parallel striae ; ribs about eleven on the body whorl ;
volutions nine, a little convex ; suture indented, distinct ; aperture
oblique, oval-orbicular ; labium concave ; color pure white, with
reddish brown spots on the striae so arranged as to exhibit longi-
tudinal and transverse series.

Ohs. The regularly arranged spots on a white ground, give
this species a very neat and delicate appearance.

It was communicated by Mr. Elliott, who informed me that it
inhabits the southern shores of Florida. PL 49, f. 1.

Cerithium septemstriatum. — Specific character. With
longitudinal costae and transverse striae; the costse bifid towards
the base ; volutions blackish, white above.

Desc. Shell turreted, with longitudinal ribs rendered some-
what nodulous by the passage of elevated spiral striae over them ;
ribs thirteen on the body whorl, their interstices much more
deeply excavated near the suture, and each divided into two on
the basal half; spiral striae on the body whorl seven, with smaller
parallel strije between them, on the second whorl are four striae,
and on the third three ; volutions nine ; suture not indented ;
aperture oblique, oval-orbicular, dark livid within and not dis-
tinctly striated ; labrum whitish on the upper margin, often inter-
rupted by small brown lines corresponding with the exterior mar-
gin slightly thickened ; labium concave, with callus at the jimction
with the labrum, and with the canal livid ; color dusky or black-
ish, the interstices of the striae often whitish, with a superior
margin to the whorls.

From Mr. Elliott. It is a very pretty shell, inhabiting the
southern coast of Florida. I think that it approaches C. zonale,
Brug., though it does not perfectly agree with Lamarck's des-
cription, particularly in not being " longitudinaliter obsolete
plicate," for the folds in our shell are so prominent and robust
as to deserve the name of ribs.

It- seems probable that Lister's figure 81, of plate 1018, is in-
tended for this shell ; to which figure Gmelin gave the name
of Murex minimus. This practice of naming figures of older

203

authors, I conceiA'e leads to error, and ought to be condemned
by every modern naturalist. Plate 49, fig. 2.

Cerithium ferrugineum. — Specific character. Pale ferru-
ginous, granulated by longitudinal ribs and transverse strire.

Desc. Shell oblong-conical with longitudinal ribs rendered
nodulous or moniliform by the passing of elevated spiral strijB over
them ; ribs about twenty on the body whorl, almost interrupted
by the interstices of the stria9 ; strire about seven, with inter-
mediate smaller ones on the body whorl, and but three on the
second whorl; volutions seven; suture inconspicuous; aperture
oblique, oval, whitish within ; labrum slightly thickened on the
exterior margin, and with obsolete impressed lines on the inner
side corresponding with the exterior striae ; color ferruginous.

Ohs. Communicated by Mr. Elliott as an inhabitant of the
southern coast of Florida. Its general form is similar to that of
the preceding species, but it is smaller, its elevations are more
rounded like granules, and its ribs are not bifid. Plate 49, fig. 3.

Mytillus. — Shell equivalve, inequilateral, obliquely elongated,
more or less ovate-acute or subtriangular, or subcuneiform, regular ;
summits posterior and terminal, acute ; anterior extremity obtusely
rounded ; posterior base a little gaping to permit the passage of
the byssus ; ligament marginal, deeply seated, subinterior, recti-
linear, elongated ; hinge edentulous, or with one or two rudiments
of teeth ; two principal remote muscular impressions, of which the
anterior one is large and elongated ; palleal impression entire.

Ohs. This genus has been considerably modified since it came
from the hands of our great master Linne, who united in one as-
semblage shells of divers characters, and constructed by animals
of opposite habits, forms and organization. Brugui^re distinguished
the widely different genera Anodonta and Avicula ; Lamarck
separated Modiola, and Leach parted from Avicida the celebrated
pearl shell of Celon under the name of Margarita, which was
afterwards called Meleagrina by Lamarck. Cuvier instituted the
genus LitTiodomus, for 31. lithodormis, and some other species
which perforate and reside within calcareous rocks. But of these
the most closely allied to the present group are unquestionably
Modiola and LitJiodomusj which two are united together by La-
marck, and are considered by Blainville only as subgenera of My-

204

tillus ; and however closely allied we may acknowledge them to
be, those genera may be distinguished by having the posterior
margin arquated somewhat prominently, the apices or beaks not
being terminal as in Mytillus. The latter naturalist gives the fol-
lowing account of the animal. " Body oval, dilated ; mantle open
at its inferior middle only, which at its anterior extremity is
fringed ; foot linguiform, canaliculate, with a byssus at its base
and many pairs of retractor muscles ; mouth with simple lips ; two
adductor muscles, of which the posterior one is very small.

Several species are eatable, and the common Muscle of Europe
(3/. eduUs, L.) is taken to market in large quantities for the table.
All the species are marine with the exception of the M. polymor-
phus, Gm., or ChevinitzU, which inhabits the Danube and the
Commercial Docks near London, but which is probably not, strictly
speaking, of this genus, if we may judge by the somewhat cham-
bered appearance of the beak cavity.

They attach themselves by means of their byssus to rocks,
stones and other fixed bodies, and even to one another. The
species are numerous ; Lamarck enumerates thirty-seven, of which
two are fossil, and several have been more recently described.
Some species are infested by a parasitical Pinnotheres.

Mytillus hamatus. — Longitudinally grooved; incurved at
base.

Mytillus hamatns, nob. Journ. Acad. Nat. Sci., vol. 2, p. 265.
Mytillus striatus, Barnes.

Obs. A very common species in the Gulf of Mexico, and i.«
carried to the New Orleans market in consequence of its parasitical
attachment to the common oyster. Hardly a cluster 6f oysters can
there be found unaccompanied by one or more and generally nu-
merous specimens of this shell, in various stages of growth. Our
figure represents a fine large specimen, in which the incurved tip
is not so remarkable as in many smaller individuals, and the form
is somewhat more elongated and less triangular. It seems to ap-
proach M. dccussatus as described by Lamarck, but in that species
the transverse striae are stated to be unequal, and its inner margin
is not said to be of a diflFerent color ; a character which in our shell
is veiy obvious. Barnes read a description of it to the Lyceum of
Natural History of New York in 1823, (see Silliman's Jouinal.
vol. 6, p. 3G4.)

205

It does not reach the attributed magnitude of M. crenafufi, Lam.,
a species which was supposed by that author to inhabit the coast of
Carolina; but if either of the different figures of Lister, Sowerby,
or that of the Encyclopa3dia Methodique is a tolerably correct
representation of it, I have certainly not met with it. PI. 50.

[Notes on 4th page of cover of part v.]

Add to the synonyms of ilf. papuana, Lam. Lister, pi. 1057.

la the observations on Sigaretjis perspectivus in No. 3, I remarked its
striking similai-ity to Cryptostoma Icachii, Blainv. On further compari-
son I find that it cannot be generically sej^arated from that species, and
the reader is tlierefore requested to alter the name to Cryptostoma per-
spectiva, nob. Analogy also indicates the change of Sigaretus niaculatus,
nob., Cryptostoma maculata. We shall in our next number give the
generic character of Cryptostoma, to be substituted for that of Sigaretus,
which latter can be retained until we publish a species of that genus.
In the 2d edition of the Regne Animal, Cuvier, in a note to the genus
Cryptostoma, says, that a species was sent from Carolina by Mr. L'Her-
menier. This was doubtless one of the above, perhaps the perspectivus,
nob., and to which he gives the name of Cr. carolinum, Cuv., not being
aware that I had long since described it.

Of Unio glehulus, N., Mr. Barabino has recently sent me some fine
specimens from Bayou Teche, one of which is four inches and three-
tenths broad, and two inches and four-fifths long.

A Venericardia was presented to me several years since by my brother,
who obtained it on the coast of New Jersey. I described it under the
name of cribraria, but as the specimen is imperfect I did not publish an
account of it. It is longitudinally ovate-orbicular, with twenty slightly
elevated ribs, more distant from each other than their width, decussated
by concentric, almost equally elevated lines. Length one inch and
about three-twentieths, and breadth one inch and one-twentieth.

Can this be a variety of the borealis of Conrad ? Having but a single
specimen I cannot determine this question.

[Am. Con., part vi., April, 1834.]

Unio nexus. — Desc. Shell transversely triangular, subrhomboi-
dal, much inflated, thick ; beaks prominent ; anterior side much de-
pressed, in its middle elevated so as to make an almost rectilinear
hinge margin, with a broad, shallow groove, which extcndsfrom the
beak to the anterior margin; anterior margin forming nearly a right

206

angle witli the b'ase, obtusely emarginate in the middle by the
termination of the groove; umbonial slope carinated, in conse-
<|uence of the depression of the anterior side ; lunule very short ;
posterior margin very short, rounded ; color light brownish, obso-
letely radiated ; within white ; cardinal teeth direct ; lateral teeth
rectilinear, short, with but little obliquity ; posterior accessory ci-
catrix obliquely elongated, slender; anterior accessory cicatrix
confluent.

Unio nexus, nob. Transylvania Journal, vol. 4, p. 527, 1831.

Unio arcxformis. Trans. Amer. Philos. Soc, vol. 4,iV". S. 1832.

The shell which we have designated by the above name is
closely related to triqueter, Raf., but differs in the greater promi-
nence of the superior portion of the anterior margin, the shorter
posterior margin and lunule, the direct cardinal teeth, and the little
obliquity of the lateral ones. It was sent to me from Nashville
by Dr. Troost. I may remark that some of the shells of Cumber-
land river vary much from their corresponding species of other
streams, if I may judge by several specimens which I have seen
from that river.

In stating the generic character, the number of muscular im-
pressions is said to be two, by which is understood, two principal
ones, for that there are many smaller ones is familiar to all those
who have examined these shells. Dr. J. G. Klees in his " Disser-
tio Inauguralis," (for which work I am indebted to Dr. L. D.
Schweinitz,) says, " musculis duobus binis majoribus clausoribus
accessoriis." Ferussac, in his '' Notice sur les Eth6ries," says,
" Presque toutes les muUttes et les Anodontes offrent quartre im-
pressions separ(?es, et Ton n'a point encore distingue d'une mani^'-re
comparative celui des muscles d'attache que dans leur position
varie acquiert une predominance sur les autres, selon la forme
de I'animale, la grosseur, ou la figure des valves." The four prin-,
cipal cicatrices of course exist in all the species of this family, but
they are sometimes so approximated in pairs as to form but two or
three separate impressions. The several smaller cicatrices in the
cavity of the beaks indicate points of the attachment of small dor-
sal muscles, for the secure support of that part of the animal. The
palleal impression is also very distinct. These dorsal cicatrices,
were, no doubt, taken into acccount by Mery, Mem. Acad. Royale
des Sci. for 1710, p. 409, who says that there are eight muscles
attached to the inner surface of the shell. PI. 51.

207

Unio apiculatus. — Desc. SlicU subquadrate, the diametei>
being subequal ; summits not very prominent : hinge margin de-
clining, and with the anterior margin compressed and separated by
an obtuse angle ; anterior margin generally retuse ; basal margin
retuse before the middle ; posterior margin rounded ; disk with a
costa from the summit descending to the anterior basal angle,
which is somewhat prominent and rounded ; behind the costa is a
much dilated groove, not very deeply impressed ; the whole sur-
face, without exception, is studded with small, subequal eminences ^
which are more or less rounded or transverse and arranged more or
less symmetrically in lines, which, before the costa, curve towards
the ligament and anterior margin, are angulated in the groove and
on the middle, and thence are arquated towards the posterior mar-
gin ; within pearly white, iridescent before ; anterior accessory
cicatrix confluent; posterior accessory cicatrix small, hardly dis-
tinct, rounded.

Unio apiculatus, nob. " Disseminator," 1829.

Unio asper. Amer. Philos. Trans., 1832.

Ohs. I obtained a few single valves of this handsome species,
from a large quantity, consisting of many wagon loads, of the
GnatJiodon truncatus, Lam., (Cy-e^ict) at New Orleans, during a
short sojourn in that city with Mr. Maclure in 1827. This vast
heap of dead and bleached shells, had been collected on the shore
of Lake Ponchartrain, and conveyed by means of small vessels
through the canal, for the purpose of covering part of the " levee "
of that city, as a substitute for a pavement. I have subsequently
received several good specimens from my friend Mr. Barabino.

In general outline and form of the disc, it has a very close re-
semblance to U. quadridus, Raf , but the surface is in every part
ornamented with crouded, elevated, more or less rounded tubercles,
not very difi"erent in point of size, and symmetrically arranged in
angulated and arquated series. Notwithstanding these differen
tial traits, I think it not improbable that when we shall become
better acquainted with this Protean genus, the apiculatus may be
considered as a variety only of the quadrulus. PI. 52.

Unio quadrulus, Raf. — Specific character. Shell subquad-
rate, tuberculated, with a nodulous ridge and dilated groove.
Unio quadrulus, Raf. Ann. gen. des Sci. Phi/s., vol. 5.

208

Unio riigosus, Barnes. SilUman's Jowrn., vol. 6, p. 126. Hil-
dreth, SilUman's Journ., vol. 14, j?. 282.

Unio lacrymosus, "| Trans. Amer. Phios. Soc, i\^. *S^., vol. 3
Tfnio aspern'mus, j and 4:.

Desc. Shell narrowed, compressed and thin before ; short, ob-
tuse, rounded and wider behind : beaks slightly elevated ; liga-
ment more elevated than the beaks ; hinge margin compressed,
carinate ; basal margin falcate, emarginate, and compressed ; an-
terior margin subangulate ; anterior dorsal margin sub truncate,
nearly straight; anterior basal margin projecting; epidermis dark
brown, under the epidermis pearly white ; sui-face rough and scaly,
wrinkled transversely and waved longitudinally, having distinct
irregular transversely compressed tubercles ; a broad nodulus, ele-
vated, somewhat double ridge extending from the beaks to the
anterior basal edge, and projecting on that part; a broad furrow or
wave behind the ridge ending in the emarginate basal edge, and a
furrow before separating the anterior hinge and anterior dorsal
margin ; cardinal teeth sulcated ; lateral tooth striated, rough, and
in the left valve somewhat double ; posterior muscular impression
deep and partly rough ; cavity of the beaks angular, compressed
and directed backward under the cardinal tooth; naker pearly
white, and on the fore part iridescent.

Oh.'i. The above is Barnes' description of this strongly marked,
common species. It is an inhabitant of the Ohio and its tributa-
ries, and approximates, by its varieties to some of the varieties of
T'. lullatus, Raf. Barnes compares it with the U. verrucosus,
Raf., to which, however, it has but a remote affinity. I have re-
ceived specimens from Dr. Hildreth of Marietta and Mr. Barabino
of New Orleans. The impressions of the plate, with Barnes' name
of rugosus, were colored before I received the " Monograph of the
Bivalve shells of the Ohio," the faithftil translation of which, Mr.
Poulson presented to me. PL 53.

Planorbis. — Shell univalve, thin, fragile, discoidal or revolving
in the same horizontal plane ; concave above and beneath, the spire,
being impressed ; aperture rounded-ovate, entire at base, the labia
interrupted by the convexity of the penultimate volution ; labrum
simple ; operculum none. Animal depressed, spiral sinistral ; foot
rounded, small ; tentaeula two, long, slender, contractile ; eyes at
the inner base of the tentaeula ; mouth somewhat exertile, armed

209

above with a lunate, simple tooth, and beneath with small cartila-
ginous hooks ; pulmonary orifice on the collar, near that of the
vent ; genitals on the same side, and separate, that of the male
near the tentaculum, of the female at the margin of the collar.

Obs. Lister first separated these shells by placing them in a
distinct section of the fluviatile kinds. In 1756 Guettard charac-
terized the genus very accurately, both the animal and its shell,
and applied to it the name by which it is now universally known.
Adanson and Geoifroy afterwards adopted the genus, the former
under the name of Gorct. Although this natural genus appeared
to be thus firmly established, our great master Linn6 subsequently
placed the species in the genus Helix, without any distinction
whatever ; an arrangement, however, in which he was not followed
by any of the distinguished naturalists who succeeded him.

Lamarck in his earlier works, placed the genus near Ampidaria,
deceived perhaps by the equivocal characters of A. cornu arietes,
which he supposed to be a Planorhis, but he afterwards referred
the genus to its true place in the family of Puhnonea aquatica,
next to Limneus. Like all the species of this family, the Planor-
his never reside in deep water, but frequent the shores where they
oan resort to the surface to inhale the air. They inhabit fresh
water and abound in various parts of the globe.

The shell of Planorhis has the appearance of being sinistral,
and this character has been almost universally stated in the generic
definition ; several conchologists, however, are now of the opinion
that it is dextral, notwithstanding the sinistral form of the animal.
Des Moulins in the " Actes de la Soc. Linn, de Bordeaux," says
that " the shell of the Planorhis is essentially dextral." Deshayes
in his account of this genus says that it is only necessary to
examine the greater number of the species and to compare them
with the dextral Limneus and sinistral Physa, to be convinced,
that in the normal position, the shell of Planorhis is truly dex-
tral ; but that the animal is really sinistral ; and he thinks we
ought rather to admit that a sinistral animal has a dextral shell,
than that the aperture is not in the normal direction, correspond-
ing with that of all shells yet discovered ; and that there is an
evident contradiction between the animal and its shell, as is also
exhibited in the Haliotis and probably in Ancylus.

The species are rather numerous, and Deshayes describes eleven
fossil species of the environs of Paris.

210

In tho following descriptions the shells are considered sinistral.

Planouijih lentub. — Dene. Shell dull brownish or yellowish
brown, sub-carinatc above, particularly in the young shell; whirls
nearly five, striate across with five, raised, subcfjuidistant lines,
forming grooves between them j spire concave; aperture large, em-
bracing a large portion of the penultimate volution ; labrum more
acutely, but not very prominently arquated above, its basal portion
horizontally Huhrectilincar in the adult and not extending below
the level of the base.

Obs. I obtained this species in the canal at New Orleans and I
indebted to Mr. Maclure and also to Mr. IJarabino for many fine
specimens collected in tlie vicinity of that city. 1 also found the
same speci(;H at Ojo de Agua, Mexico, when travelling in that
country willi Mr. Maclure. It differs from the following species
in having the labrum less prominent above, and the basal portion
of this part being in the adult horizontally subrectilinear so as not
to touch a plane on which the base of the shell may rest; the
aperture also is more tranHverse. PI. 54, fig. 1.

Planokijih TRivoJiViK. — 1*. trivolvu, S., Amcr. Ed. aj
Nlr.k(»UorC n Eacijc, ArlvMi Conckotofji/ , pi. 2, f. 2.

(JochlfAij Irmm orhium, JAatar., (Jonch. jjI. 140, /. 40.

Petiver, Gaz<yphyl. pi. lOG, /. 17.

Ohn. This is an inhabitant of the Middle and Northern States
and is very common in many districts. I have found it in Penn-
sylvania, New Jersey, Delaware, Maryland, Falls of Niagara.
Upper (JaMada,and in the vicinity of (council IJluff on the Missouri.
Dr. Eights sent me specimens from Albany, New York, and
Mr. Jossup gave several from Cayuga lake. Lister gives two
pretty good figures of this shell and quotes Virginia as the native
locality. Muller, (imelin and Dillwyn, incorrectly referred to
Jiister's figures as IliUx (dhcMd, but the latter author in his edition
of Lister iigrees with us in considering them as representations (^f
the present species. 1*1. 54, tig. 2.

I'lanoimitk IMCAHINATUK, S. Amcv. Ed. of NichohorCs Enci/i
Ai'lkle Conckolofj;//, pi. l,fif/. 4.

Helix anf/ulaluH, Racket. lAun. Trans, vol. 13, p. 42, p/. 5,

P. bicurvnafMH, Sow<rhi/» (Jciiera.

Ohs. It is an inhabitant of tho same extensive region as the

211

IrivoJuU, and was ohtjiiru'd Worn liiiko Huron I)y Mr. Racket,
whose name liad \)w\\ previou.sly iippluid in lliis ^unurt Ity Hriird.
in the Ann. du MuHouni, vol. II.

Tt IH reniarkablo Unit. Sowciilty 1ms ropnistintcMl (his mxicicK
under tlu; name of /nairiiifi/ns, a|i])ar(!iilly willioiii, Ixiin/:; iiwan;
that I hud previouHly dcscribod il, under tlici winjo nanii!. I'l. .M,
fig. 8.

Ltmnkiis Ki\lAl{(llNA'l'lis, >S'. Jimrii. AruuL Nal. Sci. vol. 1,

p.no.

Ohs. In }^(^n(M-al olxrsity i(. has a, res(!nil)laji(!() to L. iu/ldlUK,
JJrong. It was lirMtwjnt to nu; l»y IVlr. Aaron Stone I'roni the; liik(!S
of Mairu!. Dr. IJig.shy prcHcnted nie. witli a M|)(H!inien vvhieli he
obtained in njjper (lanada,, and F hav(! ree(!ntly n^eeivcid neveral
from Mr. Titian l'(;a,l(!, alwo found in Maine, one of whieh i^
doubl(! the size of the figure represented in our IMato 55, fig. I.

JiljMNKIIH (!ATAHf1()l'IIIM, S. Atticr. I'J<L of NirliokoiiH ['liirifcl.
A rtidc (!()ii<:lud()<ji/.

Obn. Its European analogue is the /y. jMrcfj/rtmi, \j., from
whieh it may be distinguished by a d(!(!p<!r fold of the coluirKjIlu,
and a more aeute eurvatiir(! of the inlerior portion of the ayier-
ture. I'l. 55, fig. 2.

LiMNKDH Di'.ci DIOHIJH, /S'. Journ. Aai'l. Ndl. Set. vol,. 2, p. I (lt».

OLh. My ))n»ther, J{. Say, snbH(!(jiienlly asefirfained it to be an
iidial)itant of Pennsylvania; found also lusar New Harmony by
LesiKMir. 1*1. 55, fig. '{.

I'kctkn. — Shell fre(!, bivalve, in(;(juivalve, thin, aurieulated,
equilateral ; hinge margin transverse, reetilinear, eonnect(!d
throughout by a ligament, the cartilage b'iing inferior, fixed in a
triangular fosset of eaeh valve, under the apex ; apices c(jntiguouH,
not elevated ; muscular impression largo, subeentral ; palleal im-
pression without sinus : animal subor})i(;ular ; foot very small, some-
tim(!s with a byssus ; mantle fringed with tenta-eular papilhe, of
whieh the scries is iriterrupted somewhat regularly by shorter
cylindrical proc«!Hses ttirminating in oeuliform disks; mouth large,
transverse, surrounded with fringed lobes, and with a thin lam(d-
lated palp on each side ; anus free ; branchiiw largr;.

Ohn. The numerous species of shells which form this very
beautiful and natural genu,s, inhabit alirio.st universally the mar-
gins of the marine portion of the gIob<;, from the torrid zone to

212

the inhospitable shores of the Polar seas. Attracted by the regu-
larity of their form and the beauty of their coloring, the ancients
distinguished them as a group from all other shells. Aristotle and
Pliny indicated several species, and compared them to a comb or
pecten from the similitude of their ornamental rib-formed radii.
Distinguished artists have judged them worthy of representation
on their canvas, and the voluptuous form of Venus is seen sup-
ported on the waves by the valve of a 2^ecten. A beautiful species
which inhabits a portion of the Pacific is deified by the natives of
some of the islands in that ocean. In Catholic countries they are
commonly called Saint James' shells, and the pilgrims who visited
the shrine of St. James of Compostella, in Spain, were careful to
attach one or more to their dress, collected on the neighboring
shore, where they abound.

It is not a little surprising that although all the earlier writers
separated these shells from others as a natural group, yet our great
master Linn6 placed them in his genus Ostrea, notwithstanding the
striking difierence in the structure of their animals, already indi-
cated by Lister and others. Bruguiere corrected this error and
restored them to the just rank of a separate genus, now universally
acknowledged. The family of Pectinides to which it belongs is
composed of the genera Lima, Plagiostoma, Pedum, Pecten, Hiii-
vite, Plicatida, Spondylus and Podojjsis. The latter is so nearly
related to Spondylus, and Plagiostoma, so closely resembles Lima,
that it has been proposed to suppress them both, which would leave
but six genera. Sowerby insists that Ilinnite cannot be a separate
genus, but must be united to pecten. Of these the three first only
are symmetrical, and furnished with a byssus. The apices of Lima
are distant and the auricles are similar in both valves. The liga-
ment in Pedum is inserted in a canaliform fossct on the inner face
of the summits, prolonged into the interior.

The ears of Pecten are equal in some species and unequal in
others, but generally on one of the valves one of the ears is deeply
emarginated beneath, to admit the passage of the byssus, by which
the animal attaches itself to foreign bodies, as represented by
Reaumer in Mem. Acad, lloyale des Sc, 1711, pi. 2, fig. 12.
Some species have a small divergent tooth on each side of the
cardinal fosset in one valve, and corresponding depressions in the
opposite valve. In many species are several very small tubercles

213

or teeth, at the base of the emarginated ear extending from near
the apex to a point beyond the ear.

Many of the Mollusca are fixed during life to one spot, others
glide along with a slow and regular snail-like movement ; but loco-
motion in this genus is rapid, and by a succession of springs or
leaps. An alternate motion of opening and quickly and forceably
closing the valves, enables them to rise to the surface, and they
sometimes make small leaps above it in ricochet. When left upon
the beach by the recession of the tide, they regain the water by
the same action. Mr. Lesson immersed a basket of Pectens in the
water of the sea, within about six inches of its rim. The individu-
als, he says, which formed the superior layer, constrained in their
movements by those that were beneath, after many fruitless efi"orts,
succeeded in leaping from their prison. No sooner did they fall
upon the water, than by striking their valves rapidly togethei,
they ran or rather skipped a few seconds upon the surface and
then sunk to the bottom. In this way all the contents of the ba:?-
ket disappeared within fifteen minutes. Smellie repeats from Pliny
that " when the sea is calm, troops, or little fleets of Scallops, are
often observed swimming on the surface. They raise one valve of
their shell above the surface, which becomes a kind of sail, while
the other remains under the water, and answers the purpose of an
anchor, by steadying the animal and preventing its being overset.
When an enemy approaches, they instantly shut their shells,
plunge to the bottom, and the whole fleet disappears !" We have
not learned that this remarkable flotilla has been observed since
the time of Plin}^

Many of the species are esteemed as food and are exposed for
sale in the markets. They are commonly known by the name of
Scallop, and the English collectors call them Fans in allusion to
their form. D'llerbigny says that in Italy they are called ca/>f
sante, in Holland mantels ; in Languedoc coquilles lar^e, in Brit-
tany and Lower Normandy, Kofiches. Deshayes enumerate," two
hundred species, more of which are fossil than living.

Pecten islandicus. — Specific character. Shell suborbicular,
with numerous rays; orange or rufous, with darker concentric
bands.

Ostrea islandica, Mvller. Chem. and Mart. Conch, vol. 7, p.
314 and SIS, pi. 6b, Jig. 615 and 616. Gmel Lam. an. sans vert.
p. 471. Desh. Encycl Meth. p. 12^, pi 2\2>,fig. 1.

214

Ostrea cinnaharina, Born. Mus.p. 103. DiUw. Catal. p. 256.

Pecten pealeii, Conrad. Marine Conch. p. 12, pi. 2,/. 2. Lister,
Conch, pi 1057, fig. 4. (The ears are represented as being equal.)
Seba, Mas. pi. 87, fig. 1. Olaffsen, Voyage, pi. 10, fig. 1,
{Huitre.^

Desc. Shell with very numerous, elevated somewhat scaly ra-
diating lines, alternately smaller, increasing in number according
to the growth of the shell to upwards of an hundred ; intervals re-
ticulated ; ears unequal, beneath the emarginated one are five or
six little teeth ; valves not very unequal, of a reddish or orange
color, with many concentric or darker bands and about three paler
radii; on the flatter valve the colors are much paler; edge jagged
with the produced elevated lines ; within the convex valve is a
large purplish spot, sometimes occupying a considerable portion of
the surface.

Ohs. Several fine specimens were sent to me a few years since
by Dr. Harris, who obtained them from Dr. Bass of Boston ; they
were taken by fishermen in Chaleur's bay, New Brunswick. Dr.
Storer has not yet found it near Boston.

Mr. T. Peale presented a specimen, which he found on the coast
of Maine. According to Dillwyn it has been found on the coast
of Scotland, and Banks procured one from the stomach of cod fish
f)n the banks of Newfoundland. The late Mr. S. Coates of Phila-
delphia had an individual in his collection, which was drawn up
on the lead by Capt. Coffin, in fifty-two fathoms water, on the
eastern edge of the banks of Newfoundland in latitude 45 deg.
40 min. Linne obtained it at West Gothland, and Olaffsen in
Iceland.

It varies much in depth of coloring, and one in my collection
has the convex valve dark purplish both within and without, des-
titute of bands, and the opposite valve is tinted with purplish
within on the upper half Mr. Peale's specimen is more of an
uniform dull orange both within and without, and with but little
appearance of bands. PI. 56, fig. la.

Peoten dislocatus, S., Journ. Acad. Nat. Scl. vol. 2, p. 260.

Encycl Meth.,pl. 213,/. 3.

Ohs. The specimen represented in the annexed plate I obtained
on the coast of South Carolina, where it is rare. I do not know
tliat the figure referred to above has been quoted by any author

215

oxoepting Dillwyn under the P. operculark, L. Mr. Conrad con-
siders the dislocatis as identical with the imrpuratus, Lam. Plate
56, fig. 2, 2a.

NASSA.-Shell univalve, subovate, ventricose, or subturreted,
acute; aperture suborbicular, emarginated and reflected at base •
abium with a more or less dilated callosity or calcareous deposite •
labrum striated or sulcated within; operculum horny ; animal de^
pressed : tentacula two, conie-cylindric, inflated at the eyes • eves
near the exterior middle of the tentacula ; proboscis very short or
obsolete; mantle folded into a distinct tube before; orifice of the
oviduct situated on the right at the opening of the branchial
cavity; branchia3 pectmiform, unequal, nearly parallel; male organ
on the right side of the neck; anus on the right; foot laro-e
prominent and angular before, attenuated behind

Ohs^ Deshayes informs us that Klein first used this generic
term for some shells of a reticulated surface, having a fancied
resemblance to the "Nasse d'osier" or willow net of fishermen
J^amarck, however, first separated the present genus from the Lin-
n^^nBuccmnm, but has subsequently reunited it as a subgenus
In this arrangement many distinguished authors coincide, as
tuvier, Blainville, Ferussac (in his Tabl. Syst.) and Deshayes.
bowerby and some other naturalists still separate it as a distinct
genus nearly related to Cassis: Montfort carries the division still
furthei^ and divides the ^ssse into FJios, Alectrion and Cyclops
and Schumacher has also separated from it a few, species, under
the name of Nana, neither of which have been admitted by
the best authorities; and it is not improbable that iVa.sa itself
may be ultimately admitted universally as only a subgenus oi Bx,^-

ctnum.

The species are numerous and are both recent and fossil They
feed on animal food and they sometimes devour the animal of
some bivalve shells such as Tdllna altemafa, S., and one of the
valves of this species often exhibits a neatly formed, round per-
foration, near the umbo, bored by a mssa. These shells ' are
sometimes smooth, but more generally with impressed strict or
grooves; others are reticulated so as to appear granulated or tuber-
culated.

A remarkable, depressed and even transverse species, the neintea
L., of which Montfort formed his genus (7ycfops, diflfers so much

216

in appearance from the usual fornij that Grmelin considered it a
variety of vestiarius, L., the type of the genus Rotella, and I ob-
served it in a cabinet, arranged with species of that genus, from
which it is in reality so widely distinct.

Nassa unicincta, S., Jour. Acad. Nat. Sci. vol 5, p. 211.

Obs. I am indebted to the late Mr. Stephen Elliott for this
species, who found it on the coast of South Carolina. In the col-
lection of the Academy of Natural Sciences of Philadelphia is a
shell from the Antilles, resembling this, and although the striae of
the labrum are double in the former, yet it is probable that the
two shells will be found to constitute one species when more
specimens shall be examined and compared. Plate 57, f. la.

Nassa vibex, S., Jo^ir. Acad. Mat. Sci., vol. 2, p. 231.

Obs. I obtained a few specimens on our southern coast, and
my brother brought me one from the coast of New Jersey. I have
since received a very perfect individual from the Academy of
Natural Sciences, and several specimens from Dr. Ravenel, of
Charleston, a gentleman who has devoted much attention to the
shells of that region and to whom I am indebted for numerous in-
teresting species. Plate 57, f. 2.

Nassa acuta, S., Jo^ir. Nat. Sci., vol. 2, p. 234, pi. 5, fig. 3.

OsTREA. — Shell bivalve, attached, foliaceous, inaequivalve, ir-
regular ; apices becoming very unequal by age, the position of
the superior valve being gradually changed with respect to the
lower valve produces a corresponding elongation of the inferior
apex ; superior valve depressed ; inferior valve larger, concave ;
hinge without teeth, tripartite, the middle portion in the inferior
valve being a longitudinal groove for the reception of the cartilage,
corresponding with a convexity of the upper valve ; ligament at-
tached to the lateral portions ; muscular impression one, large,
subcentral.

Animal depressed, margins of the mantle thick, not adherent,
retractile, with a double range of short and numerous tentacular
filaments; labial palpi long triangular ; foot none; muscle bipartite,
subcentral, no prominent syphon and no byssus.

Obs. Oysters are familiar to the knowledge of all those who re-
side in maratime districts, in almost every part of the globe. Under
a rugged and irregular exterior is included an animal which supplies

217

the most delicate food, and which has accordingly been eagerly
sought for in all ages, as one of the chief luxuries of the table.
Although the consumption of them has been immense from the
time of the Romans to the present day, yet such is the rapidity
of their increase, that their abundance does not appear to be
limited. It is believed that the Romans first devised the present
method of improving their good qualities, by transporting them
when young to favorable situations, where there is an admixture of
fresh water. The shells were used by the Athenians in perform-
ance of their right of sufi"rage, during the earlier periods of their
government, and the sentence of condemnation or acquittal of the
arraigned, was marked upon a shell ; whence the word ostracism
had its origin.

The oysters of England are held in higher estimation than those
of Germany, France or Italy. We are informed that a foreign
embassador at the Hague gave a sumptuous entertainment, during
which oysters were introduced, that were supposed by their color
to be from England. But all who ate of them were immediately
seized with violent and continued vomiting. On enquiry it was
ascertained that the oysterman had tinted the common oyster with
verdegris, to obtain a higher price for them as English oysters.

It is related of Apicius that he had a method of presei-ving oys-
ters for a long time, and that he sent them from Italy to the Em-
peror Trajan in Persia, as fresh as the day they were taken from
tlie water. There is doubtless some exaggeration in this, and it is
probable that his method may not have been preferable to that of
our oystermen, who transport the animal in kegs to great distances.
Aldrovandus and others of the earlier writers, entertained a singu-
lar and erroneous notion relative to the crab and the oyster. They
state that the crab, in order to obtain the animal of the oyster
without danger to their own claws, watch their opportunity when
the shell is open, to advance without noise and cast a pebble be-
tween their shells, to prevent their closing, and then extract the
animal in safety. " What craft !" exclaims the author " in ani-
mals that are destitute of reason and voice." We scarcely need
to add, that the craft existed only in the imagination of a person
who may have seen a crab feeding on an oyster that had fortuit-
ously closed on a pebble.

In the acceptation of Linne the genus Ostrea included numer-

17

218

ous species of various types of organization and exterior character,
although Lister had already circumscribed the boundaries with
correctness. From Linne's genus, Bruguiere separated Pecten,
Perna and Pedum, which are provided with a byssus. Lamarck
conducted the analysis still further and formed the genera Gri/-
phsea, Lima and Malleus. Of these the two latter are attached by
a byssus. Lamarck gives the following characters to his family of
Osiracea : " Ligament interior or half interior. Shell iiTegular,
foliaceous, sometimes papyraceous." It comprehends his genera
Gryphsea, Ostrea, Vulsella, Placuna and Anomia. The two
latter have the ligament interior, and Vulsella, which is closely
allied, is imbedded in sponges, and has a cardinal callosity in each
valve, extending somewhat interior. Grypli?ca is now by most
authors considered as a group of the present genus, distinguished
from the others only by the curved umbo, and I may remark that
I possess an individual of 0. virginica, which has the incurved
apex of Gryphsea.

In the generic character we have mentioned but one muscular
impression. There is, however, at least one other, which is very
small, and situated near the hinge for the support of the back of
the animal.

Ostrea equestris. — Desc. Shell small, with transverse wrin-
kles, and more or less deeply and angularly folded longitudinally;
ovate-triangular, tinted with violaceous ; lateral margins near the
hinge with from six to twelve denticulations of the superior
valve received into corresponding cavities of the inferior valve ;
superior valve depressed but slightly folded ; inferior valve eon-
vex, attached by a portion of its surface, the margins elevated,
folds unequal, much more profound than those of the superior
valve ; hinge very narrow, and curved laterally and abruptly.

Ohs. This small species is remarkable for the very abrupt lateral
curvature of the beak, the continued line of which may be
traced in favorable specimens on the exterior and inferior part, of
the umbo.

I obtained several specimens on the coast of Florida, attached
to various objects, and Dr. Ilavcnel of Charleston sent me the
individual represented in the upper part of the plate. It is
seated on a Conopea elongata, S., which is attached to a branch of
our common Grorgonia. He obtained it at Sullivan's island. The

21^

tendency towards the depressed spiral form in this shell, evinced
by the ^great obliquity of the cardinal portion, which hardly pro-
trudes beyond the margin, would arrange it with the genus Gry-
phsea in the estimation of some authors ; a group, however, which
we consider as a mere subdivision of the present genus. On the
lower part of the plate is represented one of many specimens
which I obtained in Florida attached to various objects. It seems
to be closely related to a fossil of Virginia, to which Mr. Conrad
has given the name 0. solea, but as my specimen of that shell is
imperfect and I have not his description, \ cannot determine the
degree of affinity ; it may possibly be a variety of that species.
I have also a specimen from the Antilles, and another that is re-
versed. Plate 58.

Cytherea. — Shell bivalve, equivalve, inequilateral, suborbicu-
lar, trigonate or transverse ; four cardinal teeth on one valve, three
of which diverge from the summit and one is isolated, situated
under the lunule; three divergent cardinal teeth upon the other
valve, and a fosset at a little distance, parallel to the lunule mar-
gin ; no lateral teeth.

Ohs. A genus of beautiful marine shells, included by Linnc in
the genus Venus, but separated by Lamarck in consequence of the
middle tooth of the hinge being profoundly divided into two, and
the posterior tooth being distant and parallel to the lunule edg'e.
The name of Meretrix, which that author first applied to this genus,
he subsequently thought proper to reject in favor of the present
designation. An allied genus, the Astarte of Sowerby (^Crassma,
Lam.), has but two teeth in each valve. Cijdas, Cyrena and
Megadesma have remote lateral teeth ; Cyprhia has one remote
lateral tooth, and the posterior muscular impression of Lucina is
elongated.

The species are numerous, inhabitants of almost every shore,
and are imbedded in many fossil localities. The Japanese and
Chinese paint and gild the inner side of C. lusoria with vari-
ous devices, and make use of it in their games of chance, whence
its name.

Cytherea albaria. — Desc. Shell transversely oblong-ovate,
nequilateral, wrinkles of growth more obvious towards the margin,
omewhat polished, with a slight appearance of rather broad, nu-

220

merous radii ; beaks a little prominent in consequence of tlie con-
cave curvature of the posterior dorsal margin ; lunule rather large,
impressed, distinct, oblong-cordate ; posterior side prominent ; an-
terior dorsal margin slightly arquated depressed towards the beaks,
obtusely carinated on the submargin ; anterior tip naiTowed and
rounded ; within, margin simple ; fosset of the posterior tooth
simple.

Ohs. This fossil shell was sent to me by the late Mr. Stephen
Elliott who informed me that it was found on the banks of the
Santee river, below the confluence of the Congaree and Wateree
rivers in South Carolina. It is proportionally broader than C.
Ulacina, Lam., and much less broad than C. gigantea, Gm., of
Florida. The specimen is very much thickened within on the
inner side of the palleal impression, which is deeply sinuous an-
teriorly. Plate 59.

Petricola. — Shell bivalve, transverse, subtrigonate, or oblong,
inequilateral, rounded behind, anteriorly narrowed and a little
gaping 5 hinge having one or two teeth on each valve, or upon
one of the valves only ; palleal impression profoundly sinuous an-
teriorly.

Animal with two syjjhons, divided only at tip, unequal in
length and diameter, contractile within the shell ; mantle thicker
on the margin and united, with a very small opening for the rudi-
niental conic foot; mantle very small, transverse, chiefly con-
cealed by two lips, which are extended laterally into small triangu-
lar palpi.

Ohs. Lamarck in his last work, united Rupellaria of Bellevue
to his Petricola, in his family Litliaphagu, which, as its name
implies, contains those genera of shells, which are destitute of
accessory pieces and have the remarkable property of penetrating
calcareous rocks and thus establishing for themselves a permanent
and secure dwelling. This family consists of three genera, Saxi-
cava, Petricola and Venrnqm, which are closely allied. The
hinge of the former is destitute of teeth, or in some instances has
only obsolete tubercles, and the syphons of the animal are longer
than in the present genus, and united to the extremity in one fleshy
envelope, not retractile within the shell, but always in part exposed.
Veneriipis approaches nearer to Vc7ms in the number of its teeth,
which, however, are not divaricated as in the latter genus.

221

The means by wliich these animals penetrate dense calcareous
substances, has been discussed by many able writers, without a
satisfactory solution of the problem. Some have Supposed that
the operation is eifected by the friction of the valves of the
shell ; but the valves of some species are very thin and not so
dense as the substance they penetrate, and never exhibit any
abrasion of their attenuated edges. Others contend that a pecu-
liar acid or solvent must be secreted by some appropriate organ,
which dissolves the rock by a chemical action ; but neither
anatomy nor chemistry have exhibited proofs in support of this
opinion, and in this state of uncertainty we are still left to con-
jecture and analogy. We know that the power of penetrating
calcareous substances, as well as wood and extremely dense
earth, is not confined to animals of this family, but that many
others bore through shells to devour the inhabitant, with too
small a hole to admit any part of their own shell, and numerous
other species, as their whirls revolve in the growth, remove the
asperities of the preceding volution as the aperture approaches
them. This efibct is observable in almost all rough univalve shells ;
some, indeed, cover their slight inequalities with the calcareous
deposite of the labium, but whenever the inequality is prominent,
it is sui-e to be removed at the aperture, and it would seem that
the operation may possibly be, in some instances at least, effected
by the constant action of the soft parts of the animal, or by the
agency of absorbents acting on the ultimate particles. This opera-
tion is by no means extraordinary, as every anatomist is aware that
the bony portions of the animal frame are universally modified by
the action of the softer parts. In many of the Annclidcs we find
animals of a very soft, almost gelatinous structure, penetrating the
hardest calcareous rocks, and into the substance of the thick valves
of many shells. These analogies lead us to the conclusion that
the Lithophaga excavate a lodgement in solid substances not by
the friction or boring of their shells, but by the operation of their
soft parts upon them, and not, as a distinguished naturalist has
recently supposed, exclusively by maceration of their animal mu-
cus. There are, however, some facts which seem to indicate the
presence of a solvent. Mr. Osier has a specimen of a bard cal-
careous rock in which small masses of silex remain in relief on
the sides of excavations formed by Saxicava rugosa and Venerupu

222

I'rus ; and anotlier specimen of lime mixed with argil, in whicli
the progress of three JSaxicavas was arrested by a thin layer purely
argillaceous.

Petricola pholadiformis, Lam., An. sans Yetehr., vol. 5,
p. 505. Sowerhy's Genera, pi. Petricola, fig. \ and 2. ConracTs
Marine shells, pi 7. Desk. Enc. Metli. p. 747.

Petricola fornicata, S. Journ. Acad. Nat. Sci., vol. 2, p. 319.

Ohs. This shell may be truly said to be an extraordinary species,
having the deceptive exterior aspect of a Pholas, and like many of
that genus residing in cavities drilled out of the most compact
earth, as is also sometimes the case with the P. ochroleuca. Lam.

It is abundant on many parts of our coast from Maine to Florida.
Dr. Eavenel sent me specimens from Charleston, and Dr. Storer
informs me that it is common at Chelsea and Martha's Vineyard in
Massachusetts. Plate 60, fig. 1.

Petricola dactylus, Sowb. — Desc. Shell transversely oblong-
oval, white, with radiating raised striae, which on the posterior
half of the shell, from twelve to eighteen in number, are larger,
and approximate, those of the anterior portion of the shell, filifonn,
the transverse striae are undulated on the anterior part of the
shell ; basal margin arquated ; teeth two in the right valve and one
prominent one in the left.

Petricola dacti/liis, Sowerb?/'s Genera, pi. Petricola, fig. 3.

Ohs. For this species I am indebted to the kindness of Dr.
Ravenel, who distinguished it from the preceding as a separate
species. The largest specimen in my possession measures nearly
two inches in breadth. It resembles ih.eplioladiformis,\)Vit\BO.
more robust shell, being less transversely elongated, the base more
arquated, the larger striae are more numerous and destitute of
vaulted scales, and the teeth are quite different. I had distin-
guished it by the name ai flagellata, but on a more close compari-
son with Sowerby's figure and very short description, in which no
locality is given, it evidently approaches that species, and is pro-
bably identical. PI. 60, fig. 2.

Cryptostoma. — Shell ear-shaped, univalve, spiral, very much
depressed ; spire hardly elevated above the general curvature,
lateral ; aperture very large, oblong, entire, embracing a portion of
the preceding volution } labrum simple ; volutions two or three ;

223

columella sliort, spiral : nacre none ; muscular impressions two,
lateral, distant; a slightly revolving, elevated line on the inner
surface; operculum none.

Animal tongue-shaped, chiefly formed by a very long, and very
thick foot, which is narrower and massive before, truncated behind,
canalieulated on each side and widely margining on all sides the
contorted visceral mass, which is very small, slightly convex above,
and covered by an interior shell; head depressed; mouth very
small, concealed under the anterior and superior margin of the
foot; teutaeula two, compressed and appcndiculated at base; a
large branchial pecten ; male organ under the right tentaculum ;
mantle without emargination.

Obs. That able anatomist, Blainville, was the first to detect the
difference between the animal of the much depressed species of
the genus Sigaretus, Adans., and of those with a more elevated
spire ; and notwithstanding the similarity of the shells he very
judiciously separated them and formed the present genus, if we
may judge by the characters he has stated, for which we rely en-
tirely on his accuracy. It differs much from Coriocella, Blainv.,
the animal of which has a very small foot and a coriaceous shell.

C. PERSPECTIOUS, S.
G. MACULOTUS, S.

-In attempt to exhibit a Synonymy of the Western North American species of

the genera Unto and Alasmodonta.

UNIO.

1. U. NIGER, Eafinesque.* 5. U. fragilis, R. Sw. Deshayes.

cuneatus, Barnes. gracilis, B. Hildr. Lea. Eaton.

2. U. CARiosus, S. Lam. B. ^- U- nervosus, R.

viridis,niii. zigzag, -Lq^.

siliquoides, B. (var.) donaaformis, Lea.

radiatus ? Gm. ^_ U. l^evigatus, R.

, „ „ . castaneus ? Lea.

3. TJ. FASCiATUS, Raf.

carinatus, B. 8. U. rectus, Lam. Valenc. Eaton.

latissimus, R.

4. U. LEPTODON, Raf. proelongus, B. Hildr.

planus, B.

purpurescens, Swainson. 9. U. dilatatds, R.

tenuissimus, Lea. nasutus, Lam.

gibbosus, B. Hildreth.

* This writer and some others imitated Lamarck in giving the specific name in
this genus a feminine termination, which we have changed in this table.

224

10.

11.

12.
13.
14.

15.

16.

17.

18.

19.
20.

U. CYLiNDRicus, S. B. Hildf. 24.

naviformis, Lam. Blainv. Va-
lenc. Desh.

solenoides, R.
U. CARDIUM, R.

ventricosus, B.

occidens, Lea.

subovatus, Lea. (var.)

capax, Green, (var.)

U. METANETRUS, R.

nodosus, B. Hildr.

U. OVAT0S, S. Lam. B. Hildr. Va-
lenc.

U. PASCIOLUS, R.
miiUiradiatus, Lea.

U. ALATUS, S. Lam. B. Hildr.
Desh. Eaton.
mcff(ij>ierus, Raf.

25.

U. REFLEXUS, R.

cornutus, B.

26.

U. RETUSUS, R.

stapes ? Lea. (var.)

27.

U. FLEXUOSUS, R.

pileus, Lea ?

28.

29.

U. NODULATUS, R.

pustulaius, Lea.

U. QUADRULUS, R.

ruffosus, B. Hildr.
lacrymosus, Lea.
asperrimus, Lea.

U. TRIQUETER, Raf. 30.

trianffularis, B. Hildr. Eaton.
cuneatus, Sw.
formosus, Lea. (var.)

21.

22.

23.

U. TRUNCATUS, R.

undaius, var. a Barnes.
elcgans, Lea.

U. INTERRUPTUS, R.

brevidens, Lea.

U. LINEOLATUS, R.

depressus, R. (young.)
securis, Lea. Desh.

TJ. ELLIPSARIUS, R.
elliplicus, B.
crassus, S.

U. FASCIOLARUS, R.

crassus, Wood?
ponderosus, Gray.

mucronatus, (young,) B.
pha.ieolus, Hildr. S.
planulalus, Lea.

U. VERRUCOSUS, R.

tuberculatus , B. Hildr.

U. FLAVOS, R.

rubiffinosus, Lea.
U. CYPIIIUS, R.

(xsopus, Green.

31,
32.

33.
34.
35.
36.
37.
38.

U. NODULOsus, Wood, Dillw.
biillatus, R.

verrucosus, B. (var.) Valenc.
verrucosus albus, Hildr.
pustulosus, Lea.

U. TUBERCULATUS, R.

verrucosus, B.

verrucosus pu7pureus, Hildr .

tuberculosus, Valenc.

U. SUBROTUNDUS, R.

rotundatus ? Lam.
orbiculntns, Hildr.
■ circulus, Lea.

lens ? Lea. (young var.)

U. OBLIQUATUS, R.

sulcatus, Lea.

U. TRIANGULARIS, R.

ellipsis. Lea,

U. SCALENIUS, R.

decisus? Lea. (var.)

U. OBOVALIS, R.
cbenus. Lea.

U. STEGARIUS, R.

irroralus, Lea.

U. MYTILOIDES, R.

caridiacea, Saj' of Guerin.
pyramidatus, Lea.

225

39. U. CUNEATUS, R.

paUilus, Lea.

40. U. GIBBOSUS, R.

perplexus.

41. TJ. COSTATUS, R.

peruvinnus? Lam.
U7idulatus, B.

42. U. TERES, R.

anodontoides, Lea.

^^ ^^ 52. U. NEXUS, S.

43. U. OHiENSis, R. (Anodonta.) arcoeformis, Lea.

lavissimus, Lea. (Symphonota)

infiatus? Lea. ( " ) var. 53. U. poi.itus, nob.

suhrotundus, Lea. (not Raf.)

48. U. APICULATUS, S.

asper, Lea.

49. U. LAPILLUS, S.

fabalis, Lea.

50. U. MONODONTUS, S. EatOH.

soleju/ormisj Lea.

51. U. METALLICUS, S.

cuprinus, Lea.

44. U. LATus, R. (Anod.)

dehiscens, S.
oriens, Lea.

45. U. HEROS, S.

undulaius, S.
muK/plicatus, Lea.

46. U. LUGUBRIS, S.

ater, Lea.
atra, Desh.

47. TJ. IJJTERRUPTUS, S.

trapezoides, Lea.

54. U. CICATKICOSUS, S.

varicosus, Lea.

55. U. PLiCATus, S. B.

rariplicatus, Lam. Blainv.Desh.

5Q. U. PARVUS, B. Eaton.
glans ? Lea. (var.)

57. U. UNDATUS, B.

trigonus, Lea.

58. U. SUBROSTRATUS, S.

iris. Lea.

1. A. MARGINATA, S. B.

U. ealceolus, Lea.

ALASMODONTA.

2. A. COSTATA, R.

rugosa, B. Hildr. Eaton.

3. A. COMPLANATA, B. Hildr. Eaton

[From 4tli page of cover of p. iv.]

Pecten vaeius, L.— A specimen of this shell was presented to me
several years since by Mr. Lesueur, as having been found by himself on
the Northeastern coast of the United States. I have not learned that
another has been obtained on our coast.

It seems probable that Helix irrorata, is a variety of Helix lactea,
Mull., with which I compared it when describing it. I have a shell
from Rio Janeiro, presented by Mr. T. Peale, that corresponds in all its
character with the latter species. Mr. Hyde also sent me the same
shells, from near Buenos Ayres, so that the lactea, like the aspersa and
some of the smaller species, seems to be very widely distributed.

Melania SEMrcARmATA, nob., pi. 47, add to the synonyms of this spe-
cies, M. acuta, Trans. Amer. Philos. Soc. vol. 4, N. S.

226

Valtata areijifera, Trans. Amer. Philos. Soc. vol. 4, N. S. In the
Wissihickon and other streams of water in the vicinity of Philadelphia
is the larvae of a common insect belonging to the Ltnnsean genus Phry-
ganea, which constructs a spiral follicle precisely similar to the descrip-
tion and figure above referred to, excepting, of course, that it is destitute
of operculum, which the author says, in two of his specimens was
" sufficiently perfect to exhibit a striated horny structure." The oper-
culum seems to have been imperfect in both specimens, and we fear that
a mistake may have been made, and that the V. arenifera, is in reality
only the follicle of a larva and not the production of a molluscous ani-
mal. It would be easy to make the necessary comparison, as thfe
follicle is well known to most of the conchologists of that city.

Caracolla helicoides. ibid, is a variety a of Helix palliata, S., H.
denotata, Fer.

Helix carolinensis, ibid, corresponds by description and figures with
H. appressa, S., var. a.

Melania tuberculata, ibid, is a variety of M. stygia, S.

MeIiAnia elongata, ibid, seems very closely related to M. elevata, S.,
and may probably prove to be the same.

[Amer.'Conch.'p. vii.]*

DoNAX VARIABILIS, nob. Joum. Acad. Nat. JSci., vol. 2,
p. 305. PI. 61,/. 1.

DoNAX FOSSOR, iiol. Jotim. Acad. Nat. Sci., vol. 2, p. 306.
m. 61, /. 2.

Cyrena CAROLINENSIS, Base. Say. — Nicholson's Encyclopedia,
{Sd American ed^'t ion,') article Conchology.

Ohs. It inhabits Mobile Bay, in the vicinity of Mobile, Ala-
bama, and occurs fossil in the Newer Pliocene of North Carolina,
near Newbern.— ED.f PI. 62.

Venus alveata. — Desc. Shell ventricose ; valves very thick,
subtriangular, cordate, with eight remarkably thick, very promi-
nent, much recurved, transverse approximate ribs, of an imiform
thickness throughout, terminating abruptly at their anterior slope
which is much impressed ; lunula cordate, included by an im-
pressed line.

* [No date is given for this part. It was printed after Mr. Say's deatli,
which occurred in Sept., 1833. — Ed.]
t [T. A. Conrad.]

227

Venus alocata, Conrad. Jmirn. Acad. Nat Sci., vol. 6, p.
264,i>?. 11, /^. 14,15.

Venus pa^ihia ? Lam. Anim. Sans. Vcrf., vol. 5, p. 608.

Obs. For an opportunity of examining this interesting species I
am indebted to Dr. Ravenel, who informs me that he obtained it
on Sullivan's Island, near Charleston, S. C It diiFcrs from V.
papilla, Linn., in not having the ribs abruptly smaller before they
reach the anterior slope ; and it does not agree with the figure in
the Encyc. Meth. of V. fasciata. Although probably recent, the
specimen has very much the appearance of a fossil, and this cir-
cumstance, combined with its character, leads me to believe that
it is the V. papMa, Lam., but certainly not thatof Linne. PI. 63.

Having examined the specimens sent to Mr. Say, I find tliem to be
fossil sliells. The species is characteristic of the Older Pliocene forma-
tion, and occurs at Wilmington, N. C. ; St, Mary's rivei', Maryland ; and
City Point, Virginia. — Ed.*

Tellina brevifrons. — Specific clmracter. Ovate, white,
tinged with yellowish ; anterior side veiy short.

Desc. Shell thin and fragile, not very convex, white, tinged,
particularly on the umbo, with pale dull fulvous ; with transverse
slender stria), and, in a particular light, obsolete longitudinal strise
are visible ; beaks much anterior to the middle, forming an angle
in consequence of the anterior and posterior hinge margins being
rectilinear to a considerable distance, the latter parallel to the
base ; anterior side short and abrupt, rounded at tip, and with a
submarginal undulation ; posterior side more than as long again as
the anterior, rounded at tip ; within much more deeply colored
with fulvous ; cardinal teeth, two in the left valve and one in the
right valve ; lateral teeth none.

Ohs. Inhabits the coast of South Carolina.

The outline of this shell corresponds with T. donacina, Lin.,
but is more convex, and not radiated with reddish. Dr. Ravenel
informs me that it is very rare. He obtained but a single speci-
men, which he obligingly sent to me for examination. It also re-
sembles T. decora, Say, and may readily be mistaken for it, but is
altogether destitute of oblique strise and rosaceous radiations. PI.
(M, fig. 1.

*[T. A. Conrad.]

228

Tellina mera. — Specific character. Ovate-orbicular, trans-
versely striated, liinge anterior to the middle, bidentate, with a
lateral tooth in one valve.

Desc. Shell small, thin, vehite, not very convex, somewhat
regularly striated transversely ; beaks forming a rather prominent
angle ; anterior side with an obvious undulation, and rectilinear as
far as double the length of the ligament; at tip rounded ; ligament
rufous ; posterior side nearly rectilinear half the distance from the
beaks to the middle of the tip, which is regularly and obtusely
rounded ; basal margin obtusely and regularly arquated ; hinge
with two primary teeth in each valve ; posterior tooth small and
triangular ; anterior teeth thicker, obtuse and with an impressed
line on its summit ; a single prominent lateral triangular tooth in
the left valve ; sinus of the palleal impression remarkably large, in
its posterior curvature almost confluent with the tip of the muscu-
lar impression.

Ohs. Inhabits the coast of South Carolina. — Dr. Ravenel.

In a particular light it has a slight appearance of longitudinal
lines. PI. 64, fig. 2.

Tellina alternata. — Jour. Acad. Nat. Sc, vol. 2, j^. 275.

Obs. It is abundant in the Upper Tertiary or Newer Pliocene
beds near Newborn, North Carolina. — Ed.* PL 65. fig. 1.

Tellina polita, nob. — Jour. Acad. Nat. Sc. vol. 2, p. 276.
PI. m,fig. 2.

Tellina TENTA. — Specific chara,cter. Rostrum curved to the
left ; no lateral teeth.

Desc. Shell transversely oblong-ovate, fragile, a little com-
pressed, white, with a tinge of dull yellowish towards the um-
bones ; wrinkles of growth not very prominent, but more obvious on
the anterior side ; beaks a little before the middle, not much ele-
vated ; anterior side narrowed, curved to the left, at tip truncated
or obviously emarginate ; umbonial slope hardly elevated ; within
with an obsolete appearance of radiating lines ; lateral teeth none ;
cardinal teeth in the left valve prominent ; a tinge of dull yellow-
ish on the disk as on the exterior.

Ohs. Inhabits the coast of South Carolina. — Dr. Ravenel.

The proportions of length and breadth is nearly that of Tellina

*[T. A. Com-ad.]

229

nitida, Poll, but tlie beaks are rather more anterior. The anterior
side is a little more obtuse than that of T. jndcheUa, Lam., and a
little more curved to the left nearer the tip. It evidently resem-
bles T. depressa, Gmelin, but I cannot perceive any lateral tooth.
PI. 05, fig. 3.

Tellina tenuis, Da Costa. — Specific character. Shell oval-
triangular, irregularly striate concentrically; each valve with two
teeth, and one of them with lateral teeth.

Tellina tenuis, Da Costa, Brit. Conch., p. 210. Chem. 6, p
124, tah. 12, fig. 117. Donavan, t. tab. 19, three lower figures.
Penn. Brit. Zool. 4. p. 180, tah. bl,fig. 2. Mont. Test. Brit., p.
59. Turton, Brit. Fauna, p. 150. Wood, Conch, p. 155, to6. 44,.
figs. 3 and 4. Conch. Diet., p. 169. Conch. Ins. Brit., p. 107.
T. levis. List. Conch., t. 405, Jig. 251.

Obs. There may frequently be observed some very minute and
tine longitudinal white lines, from which circumstance it has been
often mistaken for T. striata ; but the lateral teeth will at all
times distinguish it, there being two small lateral teeth in one of
the valves only. We believe that the T. balaustina and T.planata
of Linnaeus are among the numerous varieties of this species. —
(Turton.)

I have copied the above from Turton's '' Bivalves of the British
Islands," believing our shell to be the tenuis of authors. Mr. Say,
unfortunately, has left no description of this species, which was
sent to him by Professor Bavenel of Charleston, who found it on
the shore of Sullivan's Island.— Ed.* PI.