^ ^

OBSERYATIONS

GENUS UNIO,

TOGBTHEU WITH

DESCRirTK)^". OF NEW ETLCJiG IN 'i^HE iAMILIES UNIOlsID^, COLDJV^lA

.'.ND MELAKIA-aA.

KJiAl) UKi'UKE THJi AMEKICA.N llULUSUl'lUCAL .SUCILI'V, AND OIUGINALLY
I'UBLISIIKD IN ITS TRANSAtXIO.NS.

i;\

1S\AC LEA,

jt.il ot ml '■ "i I I'- ■!' . I'lhNfi: III j'lii 'iiA.

-E IM,-. i.I.V!

. Ill .' u. I .\l'

WITH NUMElvUlJ? PLATES.

VOL. \

rHlLADELrHl A:

PRINTED FOR THE AUTTTOT?.
w. f. vorsa, rnnmiB.

-S

5=

10-

_D

: m

i 3-

; _D

: r^
i □
I O

■ r^

s m

B a

€

/i /Sz^

^» y« Aftademy

OBSERVATIONS

GENUS UNIO

&&

j.;ri ^^

/'V y:|

OBSERVATIONS

ox THE

GENUS UNIO,

rOaETHBB WITH

DESCRIPTIONS OF NEW SPECIES IN THE FAMILIES UNIONIDiE, COLIMACEA

AND MELANIANA.

HEAD BEFORE THE AMERICAN PHILOSOPHICAL SOCIETY, AND ORIGINALLY
PUBLISHED IN ITS TRANSACTIONS.

BY

L

ISAAC LEA,

MEMBER OF THE AM. PHIL. SOC; OF THE ACAD. OF NAT. SCIENCES OF PHILADA.:

OF THE ZOOL. SOC. OF LONDON; OF THE IMPERIAL

SOC. OF MOSCOW, iC. 4C.

WITH NUMEROUS PLATES.

. rcr.

VOL. V.

PHILADELPHIA:
I'RINTED FOR THE AUTHOR.

*-.

L

7^

\

AqL^

TO MAJOR JOHN LE CONTE.

My Deak Friend:

Will you permit me in this way to acknowledge my obligations to
your great kindness and liberality, in furnishing me, during so many years, with nume-
rous new species of our fluviatile molluscs? The pains you have always taken in
bringing to light new forms, may readily be understood by looking through this and
my previous volumes on this interesting subject. I feel grateful for the untiring assi-
duity you have given to promote my objects, and therefore it is with peculiar pleasure
that I present you with this volume.

Truly and
, Faithfully yours,

ISAAC LEA.

CONTENTS.

Description of New Species of the Family Unionidsc. Read March 5, 1852, . . Page 9

Do of a New Genus of the Family Melaniana, and New Species of Melania;,

Read March 5, 1852, ......... 51

Do of a New Species of Helix from California, Read March 5, 1852, . . 59

NEW FRESH WATER AND LAND SHELLS.*

It is now some years since I presented to this society a continuation of my discoveries
of new forms from the fresh waters and soil of the United States. Since that period,
owing to the kindness of many valued friends, I have hccn enahled to get together a much
larger number by far, than could have been anticipated. These have come chiefly from
localities hitherto little examined, and which have produced new species more or less in-
teresting. It will be observed that many are from Dr. Barratt, of Abbeville District, S. C,
from Mr. Tuomey, of Alabama, Dr. Hale, of Alexandria, Louisiana, Prof. Powell, of Mem-
phis, Major Le Conte, who procured them from Florida and Georgia, President Estabrook,
of Knoxville, Tenn., Mr. Joseph Clark, of Cincinnati, Mr. C. M. Wheatley, of New York,
and other kind friends. To them all, I return my sincere thanks for their liberality, and
I trust that they will be induced not to flag in the cause of American science, but rather
to be encouraged in the development of these new organic forms, which, in this branch
of Zoology exist in such vast profusion, and in so extended a number of species, in the
United States.

Notwithstanding the vast number of well characterized species of the Family Unionidee,
(as there are also in the Family Mclaniana,) there are continually new and distinct forms
brought to our notice, which well deserve the attention of the American Zoologist.

I am aware that many persons doubt the existence of so extended a production of
species, but this arises from the want of a knowledge of them, closely cultivated and
analytically examined. An organic form, instituted by nature must be recognised as dis-
tinct, for it will remain in a state of autonomy to the end of its term. It is the duty of
the zoologist to bring to the investigation an eye practised in discrimination, and a judo--
rnent experienced in analysis, as well as also an honest intention of purpose, that he may
give the best and most accurate results to his investigations.

[* Read before the American Pliilaso]iliii-nl Sociely, Marrli 5, 1852, and |niblislicd in llie TransaclioiLs,
Vol. X., New Series.]

10 DESCRIFTION OP NEW

Unio sordidis. pi. XII. Fig. I.

Ttita lirvi, tHijUkn, sithcompressn, ineqnilatera/i, poslice rotvndata ; vn/vulis siibcrassis ; nallbus promi-
mi/is; epidertniile riifo-fiisca, striata; dentibus cardinalibus parvis ; lateralibus longis subrectisque ; marga-
rild alba et iridescentc.

Slicll smooth, elliptical, rather compressed, inequilateral, rounded behind ; valves rather thick ; beaks slightly
prominent; epidermis reddish-brown, striate; cardinal teclii small ; lateral teeth long and nearly straight ; nacre
white and iridescent.

Ilab. Abbeville District, S. C. J. l\ Barratt, M. D.
My cabinet,
Diain. .8, Length 1.3, Breadth 2.4 inches.

Shell smooth, elliptical, rather compressed, inequilateral, rounded before and behind ; sub-
stance of the shell rather thick, thinner behind ; beaks slightly prominent and nearly terminal;
ligament long and thick; epidermis roddish-brown, obtusely rayed, with obscure equidistant
marks of growth; umbonial slope rounded; cardinal teeth very small and striate, single
in the right and double in the left valve; lateral teeth long and nearly straight, separated
from the cardinal tooth; anterior cicatrices distinct; posterior cicatrices confluent; dorsal
cicatrices nearly in the centre of the cavity of the beak, under the cardinal tooth; cavity
of the shell shallow; cavity of the beaks very shallow and subangular; nacre white and
iridescent.

Remarks. — A single imperfect specimen only of this was received by me, and I hesitated
for some time to describe it, in hopes of getting more to determine its characters better.
It is certainly very much like the widely distributed U. complanatus; but it seems to me to
differ in its form, being more rounded behind, more rounded over the umbones, and more
compressed over the umbonial slope.

Unio Gibbesianus. PI. XII. Fig. 2.

Testa leevi, cUiptica, sichcompressti, ine/juilaterati, postice snbbiangnlatu ; vtilvulis siibcmssis ; natibus
prominentibiis : tpidennide hilco-fuscn, rudial/i, striata: dentibus cardinalibtifi parvis, tripartili.i ; lulcralibus
pradongis su/)reclistjtif ; viargurilit alba et iridescenle.

Shell smooth, elliptical, somewhat compressed, inequilateral, sidibiangular behind; valves rather thick; beaks
prominent; epidermis yellowish brown, radiated, striated; cardinal teeth small; lateral teeth very long and
nearly straight ; nacre white and iridescent.

Ilab. Abbeville District, S. C. Louis R. Gibbes, M. D.
My cabinet,
Diam. 1, Length L5, Breadth 2.8 inches.

Shell smooth, elliptical, somewhat compressed, inequilateral, rounded before and sub-
biangular behind; substance of the shell thick; beaks prominent and submedial; ligament
long and very thick ; epidermis yellowish-brown, obscurely radiated, roughly striate near
the margin, smooth on the umbones, marks of growth nearly equidistant and distinct;
umbonial slope rounded; cardinal teeth small, slightly elevated, pointed and tripartite;
lateral teeth very long, nearly straight and thickened at the j)osterior end, se[)aratcd from
the cardinal tooth: anterior cicatrices distinct; posterior cicatrices distinct; dorsal cica-

1

.%u^..^/.>^.^//y:,9ec^£^c%U^^//:^Ms.

,J^Crr7e-^

/

/hivi iV.H«<>^ t, //.l,,^

I Vtuii sftrdiifiat
'J » (iibhcsuiinix
ii .. pa 'xfr-t/i/i/x

FRESH WATER AND LAND SHELLS. H

trices nearly in the centre of the cavity of the beaks, on the inferior posterior part of the
cardinal tooth; palleal cicatrices distinctly impressed; cavity of tiie shell shallow, cavity
of the beaks shallow and subangular; nacre white and iridescent.

Remarks. — It is to be particularly regretted that a single specimen only of this species
should have been received from Dr. Gibbes. The cardinal teeth in both valves arc Irlparlilc.
They are distinctly divided into three lobes, of nearly equal size and form. This is so unique
that I have inserted it with some hesitation as a permanent character, tripartition being
so unprecedented. It may possibly be accidental. Should other specimens prove this
form to be persistent, this species will present an anomaly peculiarly its own. The lateral
teeth are, as usual, single in the right and double in the left valve; but the terminal in-
ferior portion is remarkably enlarged and thickened in the latter valve, so as to run
beyond the superior portion. The marginal portion of the disc is remarkably furnished
with imbricate epidermal matter. It has somewhat the outline of U. complanalus, but may
easily be distinguished from that species by its being more elevated in the beaks, in its
imbricate margin, and in the form of the teeth.

Unio perstriatus. pi. XII. Fig. 3.

7'esld leevi, valcle transi'ersci, valde compressd, subemars^inatd, vahle inxquUaterali, poslicc siibhiana:idutd;
valvuKs tenuibus ; tiatibus parvis,vix piominentibiis, ad apkem uiididatus ; epidcnnide luteo-fuscd,per!striat(i:
denlibus cardinalibus parvis, obliquis ; lateralibus prxlongis reciisqite; margurilu alba et irUescenle.

Shell smooth, very transverse, very much compressed, subemarginate, very inequihiteral, subbiangular behind;
valves thin; beaks smal], scarcely prominent, undulated at the tip; epidermis yellowish-brown, verj- much
striated; cardinal teeth small, oblique; lateral teeth very long; and straight; nacre white and iridescent.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.
My cabinet and cabinet of Dr. Barratt.
Diam. .5, Length 1, Breadth 2.3 inches.

Shell smooth, very transverse, very much compressed, slightly cmarginate, very inequi-
lateral, subbiangular behind, obtusely rounded before, posterior slope wide and flattened;
substance of the shell thin; beaks placed near to the anterior margin and furnished with
minute undulations at the tip, scarcely prominent, but rather pointed; ligament long and
thin; epidermis yellowish-brown, with numerous imbricate striffi covering nearly the
whole of the disks, and with only one or two distant marks of growth; umbonial slope
biangular and flattened; cardinal teeth small, oblique, double in the right and single in
the left valve; lateral teeth very long, straight and thickened at the posterior ends;
anterior cicatrices distinct; dorsal cicatrices placed under the plate between the cardinal
and lateral teeth; cavity of the shell exceedingly shallow; cavity of the beaks very shal-
low and rounded ; nacre white and iridescent.

Remarks. — Dr. Barratt sent me four specimens of this species, which may easily be
distinguished by its peculiar striated epidermis, and its compressed form. It scarcely
belongs to that large group of which the U. complanalas is the type, but certainly borders
on it. The nacre of three of the specimens is white, slightly tinged with blur. The
fourtli specimen is |)urplish. The lines of growth arc very remarkable, being few and

12 DliSCUll'TlON OF NEW

very distant, neillicr of the speciiHcns liaviiig more than two, and two of tlieni having
only one hne of growth. In outhiic it closely resembles V. slri^^ostis, (Nobis,) but is a
rouifhcr shell, and thinner.

Umo Tuomevi. pi. XIII. Fig. 4.

Teslti lievi, ellipliccU sitlmmprcsiiu; vulvtilis subcrussis; natilws vix prominulh ; epidermidc luleo-fusdt ;
denlibus curdinalibus siibgrundibiis; lutcrulibus longis, aubcramsis curvisque; margurila iridetscenle, colore
salmoiiis linctii.

Sliull smoolli, elliptical, rather compressed; valves somewhat thick; beaks sligluly prominent ; epiilermis
yellowish brown ; cardinal teeth rather large; lateral teeth long, rather thick and curved; nacre iridescent,
salmon coloured.

llab. Abbeville District, S. C. J. P. Rarratt, M. D.

My cabinet and cabinets of Dr. liarratt and Mr. Tuomey.
Diam. .8, Length 1.3, Breadth, 2.G inches.

Shell smooth, elliptical, rather compressed, snbangular behind, rounded before, slightly
angular on the posterior slope; substance of the shell somewhat thick; beaks slightly
prominent, with minute undulations at the tip; ligament rather long and thin; epidermis
yellowish-brown, shining, with indistinct rays on the posterior portion; cardinal teeth
rather large, somc>\liat pointed, single in the right and double in the left valve; lateral
teeth long, curved and thickened at the posterior end; anterior cicatrices distinct; pos-
terior cicatrices confluent; dorsal cicatrices placed in the cavity of the beaks; cavity of
the shell shallow; cavity of the beaks small and slightly angular; nacre iridescent and
salmon coloured.

linnarkii. — There were seven specimens of this species among the shells sent to me by
Dr. liarratt and Mr. Tuomey. They are of diiferent ages, and nearly allied to I/. Barrattii,
herein described, but may be distinguished by being more compressed and less transverse.
All of the seven specimens before me have salmon coloured nacre, except one, which is
mixed with a tinge of purple. Other specimens may likely be found with white and purple
nacre.

Unio Barratth. pi. XIII. Fig. 5.

Test('i fievi, transversa, sxibinjiutd; valvii/is sttbcrassis; natibus vix prominuHs ; rpidermide vlrido-fiisra ^
(lenlibvs cardina/ibi/s grundibus; laleralibus longis, subcrassis sitbcurvisquc; margurild vcl alba vol purpurd
vel colore aalmonig linctd.

Shell smooth, transverse, slightly inflated; valves somewhat thick; beaks slightly prominent; epidermis
greenish-brown; cardinal teeth large; lateral teeth long, aomewhal thick, and rather curved; nacre white-purple
or salmon coloured.

ITab. Abbeville District, S. C. J. P. Barratt, M. D.

My cabinet and cabinets of Dr. Barratt and Mr. Tuomey.
Diam. .8, Length L3, Breadth 2.9 inches.

Shell smooth, transverse, slightly inflated, angular behind and rounded before, angular
nil the posterior slope, subcarinatc on the posterior dorsal margin; substance of the shell
somewhat thick ; beaks slightly prominent, with minute undulations at the tip; ligament

,j^. ^.'^^. ^^^MM/tm/3

d^-T

^^

44 I'lllfl TtlOtlU'VI .

.} liiirraiht .

6 » cfrrtn'iitns

r .Vd&tfK hr M<^itn

FRESH WATER AND LAND SHELLS. I 3

r;ilher long and thin; epidermis greenish, clouded with brown, slightly polished, with
rather minute, indistinct ra3's; cardinal teeth large, pointed, single in the right and double
in the left valve; lateral teeth long, somewhat curved and thickened at the posterior end;
anterior cicatrices distinct; posterior cicatrices confluent; dorsal cicatrices placed in the
centre of the cavity of the beaks; cavity of the shell shallow; cavity of the beaks small
and rather angular; nacre white, purplish, or delicately salmon coloured and iridescent.

Remarks. — Among many interesting species — several of which were new — received
from Dr. Barratt and Mr. Tuomey, were four of this species. One is an adult, the other
three are young. It has somewhat the outline of U. rectus, Lam., and has on the exterior
a resemblance to U. nasutus. Say, but is a thicker shell. It is not so cylindrical as the
rectus, nor so wide. It is allied to U. Tuomeyi, but is a wider species.

Unio decoratus. pi. XIII. Fig. 6.

Test a oblon2:d, vcilde compressd, insequilulerali ; valvulis sublemubus : natlbits promiimUs, cotnpreaxis, ad
apices tiudutalis ; epidtrmide luteo-viridi, densissiine radiatd; denlibus curdinulibus ptirvis, luvieltulis :
luleralibits parvis rectisrjue; margarila ulbd et. iridiscenle.

Shell oblong, niucli compresseil, inequilateral; valves rather tliin; beaks sliijlitly prominent, compressed, tindu-
lated at the beaks; epidermis yellowish-green, closely radiated; cardinal teeth small, lamellar; lateral teeth small
and straight; nacre white and iridescent.

Hab. Abbeville District, S. C. Dr. Barratt and Mr. Tuomey.

My cabinet and cabinets of Dr. Barratt and Mr. Tuomey.
Diam. .8, Length 1.4, Breadth 2.3 inches.

Shell oblong, much compressed; posterior dorsal margin carinate ; substance of the
shell rather thin, slightly thickened before; beaks slightly prominent, compressed and
crowded with double concentric undulations; ligament very small, thin, nearly concealed
within the valves; epidermis yellowish-green, with numerous capillary rays over nearly
the whole disk; cardinal teeth rather small, lamellar, single in the right and double in the
left valve; lateral teeth rather short, straight and acicular; anterior cicatrices distinct;
posterior cicatrices confluent; dorsal cicatrices situated in the point of the cavity of the
beaks; cavity of the shell rather shallow; cavity of the beaks small and angular; nacre
white, rather brilliant and iridescent.

Remarks. — I owe to tfie kindness of Dr. Barratt and Mr. Tuomey four specimens of
this interesting species, which draws more attention from the fact of its forming a natural
link with a highly interesting species which I described and figured in Vol. III., Trans,
Am. Phil. Soc, PI. XII. Fig. 22, under the name of Sijmplnjnota {Unio) comprcssa, after-
wards changed to pressus. It differs from the pressiis, however, in being less oblong, in
being rather more inflated and less lenticular. In the teeth, while there is a strong assi-
milation to that peculiar character of the pressus, there is a marked difference; the eleva-
tion of the posterior portion of the cardinal tooth being very much less, and the two bifid
portions much closed. The umbonial slope is disposed to be angular. The transverse
striae are close. The marks of growth distant. This species, like U. jtrcssus, has the
symphynote character of the w ing.

14 DESCRIPTION OF NEW

Unio rufusculus. pi. XIV. Fig. 7.

TcsU'i ftPvi, elliplicn, stibcompressii, inxriitllaleraU, postice biangulatu ; valvidis siihcrasstbvs : nttllbus sub-
jiromlnmlibus ; epUlermuh tenebroso-J'vsca, st riatc'i : detillbits cardinulibus nbluinis, parvis slrlalisque ; lulerali-
bus remolis, longis, lamellatis, rectis; margaritd vel alba vel salmonis colore linctd.

Shell snioolli, elliptical, rather compressed, inequilateral, biaiigular behind; valves rather thick ; bealis some-
u- hat prominent; epidermis dark-brown, striate; cardinal teeth oblique, small and striate; lateral teeth remote,
long, lamellar and straight; nacre white or salmon coloured.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.
My cabinet.
Diam. .9, Length 1.4, Breadth 2.4 inches.

Shell smooth, elliptical, rather compressed, inequilateral, biangular behind, rounded
before, substance of the shell rather thick, thicker before; beaks somevvhat prominent and
submcdial; ligament rather long and thick; epidermis dark-brown, obscurely rayed on the
posterior slope, striate towards the margin, with obscure, nearly equidistant marks of
growth; umbonial slope subangular; cardinal teeth oblique, small, with regular string;
single in the right and double in the left valve; lateral teeth separated from the cardinal
tooth, long, lamellar, straight, and slightly thickened towards the posterior end; anterior
cicatrices distinct; posterior cicatrices confluent; dorsal cicatrices placed rather above
the centre of the cavity of the beaks; cavity of the shell rather shallow; cavity of the
beaks very small; nacre white or salmon coloured.

Remarks. — This species belongs to the group of which the common U. complanalits is
the type. It seems to stand between it and U. Congarceus, (Nobis.) It is more angular
on the umbonial slope than complunatus, and less so than CongarcBus. Of the three speci-
mens received, two are salmon coloured. The oldest specimen is very thick and much
eroded. The youngest is rather thin. The outline of this species is very much like the
figure of Unio platii/ateris, Conrad, but it differs in the colour of the epidermis, in the
thickness of the teeth, and the obliqueness of the umbonial slope. It is also very like
U.ftihnis, (Nobis,) which also came from South Carolina; and it is possible that when
good suites are brought together, this species may prove to be only the adult of a flatter
variety o( fulvus.

Unio Whiteianus. PI. XIV. Fig. 8.

Testa Itrvi, elliplicd, hijlaiu, valde insequilateruli, postice subangitlatd ; vahulis crassis; natibus siibpromi-
nentibus; tpidermide vel tencbroso-fusca vel nigra, striata, ad apices polild ; dentibus cardinulibus magnis,
elevatis, crenulatis; lateralibus longis subcurvisque ; margaritd vel albd vel salmonis colore tincta.

Shell smooth, elliptical, inflated, very inequilateral, snbangnlar behind; valves thick; beaks somewhat promi-
nent; epidermis dark-brown or black, striate, towards the beaks polished; cardinal teeth large, elevated, crenu-
lated ; lateral teeth long and somewhat curved ; nacre white or salmon coloured.

Hab. near Savannah, Geo. Rev. G. White.

My cabinet and cabinet of Mr. White.
Diam. .1, Length 1.4, Breadth 2.5 inches.

Shell smooth, elliptical, inflated, very inequilateral, rounded before, subangular behind;
substance of the shell thick; beaks somewhat prominent; placed towards the anterior

rjiami. ,.//.. .^/-i^. .g.<:^f,j:'U/>,/<'^MM

TC J?^A'!

x,.Y

7 , ruitt 'Xiil'usrulus
8 . . il'hi/rinnns.
if. . l.osarits .

FRESH WATER AND LAND SHELLS. 15

margin; ligament sliort and tliick; epidermis dark-brown or black, roughly striate on the
margin, but smooth and highly polished on tiie sides and towards the beaks; marks of
growth rather indistinct and distant; umbonial slope rounded; cardinal teeth large, ele-
vated, crenulated, pointed, single in the right and double in the left valve; lateral teeth
lontT, rather thick, somewhat curved and separated from the cardinal tooth ; anterior cica-
trices distinct; posterior cicatrices distinct; dorsal cicatrices placed nearly in the centre
of the cavity of the beaks; cavity of the shell rather deep; cavity of the beaks shallow
and rounded; nacre usually salmon coloured, sometimes white.

Remarks. — Many of this species were sent to me by Mr. White. None of the
beaks are sufficiently perfect to detect the undulations of the tips. The form and size of
this species approaches closely to U. confertus and JJ. Geddingsianus, (Nobis.) It may
be distincuished from them, however, by the remarkable polish of the superior portion of
the disk and the beaks, and by the rough stria? of the other portion of the epidermis.
The adult specimens are all very dark-brown or black. The younger shells are yellowish,
with numerous dark-green rays over nearly the whole disk. Some of the adult specimens
are quite straight on the basal margin, and almost falcate.

Unio Lazarus. PI. XIV. Fig. 9.

Testa Ixvi, arciiald, vahle Iransversci, compressci,vakU inxquilateruli, postice sitbbitingiila/ii ; valvulis pcr-
tcnuibits; nalibiis itndulatis, vix proininen/ibun; eindermide tenebroso-fusca, rugoso-striatu ; dmtlbus cardi-
nalibiis minimis; lateralibus longis, acicvlaris, remotis reclisque; murgaritc't vel alba vcl purpurea et valde
iridescent e.

Shell smooth, arcuate, very wide, compressed, very inequilateral; subbiangular behind; valves very thin;
beaks undulated, scarcely prominent; epidermis dark-brown, roughly striate; cardinal teelh very small; lateral
teeth long, acicular, remote and straight; nacre white or purple and very iridescent.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.
My cabinet and cabinet of Dr. Barratt.
Diara. .4, Length .9, Breadth 2 inches.

Shell smooth, emarginate at base, very wide, compressed, very inequilateral, behind
subbiangular, before rounded; posterior slope wide and flattened; substance of the shell
very thin, thicker before; beaks placed near to the anterior margin, furnished with very
minute undulations at the tip, scarcely prominent and very small; ligament long and thin;
epidermis dark-brown, roughly striate, with obscure marks of growth; umbonial slope
biangular; cardinal teeth very small, crenulate, double in the left and single in the right
valve; lateral teeth long, separated from the cardinal tooth, acicular, straight and slightly
turned up at the extreme posterior point; anterior cicatrices distinct; posterior cicatrices
confluent; dorsal cicatrices small and placed under the plate posterior to the cardinal
tooth; cavity of the shell very shallow; cavity of the beaks very shallow and rounded;
nacre white or purple.

Remarks. — This is a small, very thin and fragile species. The young have very much
the appearance of the yoimg of the elongate variety of U. complanatus, but the adult
and middle aged are arcuate, and cannot be mistaken for that species. The young arc

IG DRSCRIPTION OF Ni:\V

greenish, with obsriiro rnyp, nnd tlio undulations of tlic l)enl<s arc loss pronounced than
those of the comp/aiia/tis. It is somewhat like U./ol/iciilalus, (Nobis,) but is a tliinner and
less transverse species. The older specimens are very much compressed in the middle,
near to the basal margin.

Unio merus. pi. XV. Fig. 10.

Testa Isevi, ellipticit, subinjluta; valvulis crassis; nalibus subpromincntibus, ad apices undulalis; ep'uler-
mide luted, radiatd, nitidt'i; dentibus cardinalibus magnis, crenutatis; laterulibus longis, rectis,a cardinalibiis
separatis; margaritu alba et iridescente.

Shell smoolli, elliptical, somewhat inflated; valves thick; beaks somewhat prominent, undulated at the beaks;
epidermis yellow, radiated, shining; cardinal teeth large, crenulate; lateral teeth long, straight and separated from
the cardinal tooth ; nacre white and iridescent.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.
My cabinet and cabinet of Dr. Barratt.
Diam. .G, Length 1, Breadth \Sj inches.

Shell smooth, elliptical, rather inflated, somewhat striate, rounded before and angular
behind; substance of the shell thick, thinner behind; beaks somewhat prominent, rather
coarsely undulated at the tip; ligament short and rather thick; epidermis yellow, obscurely
radiated, shining; umbonial slope subangular; marks of growth distant and distinct; car-
dinal teeth large, compressed, crenulate, pointed, single in the right and double in the left
valve; lateral teeth long, straight, lamellar, separated from the cardinal tooth; anterior
cicatrices approximate; posterior cicatrices confluent; dorsal cicatrices situated on the
under side of the cardinal tooth; cavity of the shell shallow; cavity of the beaks siDall and
angular; nacre white and iridescent.

Kemarks. — In its general character, this species resembles U. Congarseus, (Nobis.) It
is not, however, so much compressed, and the angle of the umbonial slope is much less
expressed. Of the six specimens before me, five have white nacre. The sixth and largest
is slightly tinted with salmon colour.

Unio CONGA vus. PI. XV. Fig. 11.

Testa lasvi, eflipticd, injlatu; valvulis subtcnuibits ; nalibus prominulis ; epidermide pallido-lute.olii, virldn-
sliiata; dentibus cardinalibus parvis, compressis; lateralibus longis reetisqiie; murgurita alba el iridescente.

Shell smooth, elliptical, inflated; valves rather thin ; beaks slightly prominent ; epidermis pale-yellow, with
green rays; cardinal teeth Sinali and compressed; lateral teeth long and straight; nacre white and iridescent.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.
My cabinet.
Diam. .8, Length 1.2, Breadth 2.2 inches.

Shell smooth, elliptical, inflated, rounded before and subangular behind; substance of
the shell rather thin, slightly thickened before; beaks slightly prominent, nearly medial ;
ligament rather long and thin; epidermis pale-yellow, with numerous green rays reaching
to the margin, smooth and polished, scarcely showing the lines of growth; cardinal teeth
compressed, single in both valves, and abruptly terminated: lateral teeth long, straight,

.%^.j.^^. Ml/:. 9:^. ^^-^e^e^Hf^/t^/t

\ VC .'iAi

i.h!\s't.N'Y]

Fftirri .Vtrurr *» nhot

UK I'mo miTiLS.

11, - d^trir^nnis.

12, M iinffhis-

13, „ bllX4-JtX.

PRESn WATER AND LAND SHELLS. 17

and slightly elevated; anterior cicatrices distinct; posterior cicatrices confluent; dorsal
cicatrices within the cavity of the beaks; cavity of the shell deep and rounded; cavity of
the beaks shallow and subangidar; nacre white and iridescent.

Remarks. — A single adnlt specimen only has been received from Dr. Barratt, with two
quite young ones. The beaks of one of these are sufliciently perfect to show that the
undulations extend some distance from the point, and that they are rather complex. The
young are rayed over the whole disk. The adult specimen has many dark-green rays
over the posterior portion, but none on the anterior portion. This species is somewhat
like Unio cariosus. Say, but is more regularly elliptical and more transverse. The young
specimens very much resemble the young of U. radiatus.

Unio ineptus. PI. XV. Fig. 12.

Testu laevi, cHip/icd, sitbco'mpressa ; viilvulis tcnuibiis; nalibus vlx prnminmlibus, ad apices uniluhilh:
t'pidcrmidc Valde tcncbrosa, striata; dentibus cardinalibus parvls, coniprcssis ; latcra/ibus longis, subrcctis, a
cardinulibus separatis ; margaritd casruled.

Shell smooth, elliplical, somewhat compressed; valves thin; beaks scarcely prominent, undulated at the beaks;
epidermis very dark and striated; cardinal teeth small, compressed; lateral teeth long, nearly straight and sepa-
rated from the cardinal tooth; nacre bluish.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.

My cabinet.
Diam. .4, Length .7, Breadth 1.3 inches.

Shell smooth, elliptical, somewhat compressed, rounded before and subangular behind;
substance of the shell thin; beaks small, scarcely prominent; undulated rather coarsely at
the tip; ligament short and thin; epidermis much striated, very dark-brown, nearly black;
umbonial slope rounded; marks of growth indistinct; cardinal teeth small, compressed,
crenulate, double in the left and single in the right valve; lateral teeth long, nearly straight,
thickened at the posterior end; anterior cicatrices distinct; posterior cicatrices confluent;
dorsal cicatrices placed nearly in the centre of the cavity of the beaks; cavity of the shell
very shallow; cavity of the beaks very shallow and angular; nacre bluish.

Remarks. — A single specimen only of this species is before me, and may not be adult.
It is quite small, and somewhat like U. fubalis, (Nobis,) of our western rivers, but is still
more closely allied, in general form and colour, to U.faha, D'Orb. It differs from the
former in being a thin shell, and having a more elevated posterior slope, and from the
latter in having the sides more compressed, and in the beaks having irregular undulations,
while the faba has the radiated folds so peculiar to most of the South American species.
The specimen of inepliis before me has two obscure rays on the posterior slope, none being
apparent over the disk. More perfect specimens may present rays.

Unio buxeus. PI. XV. Fig. 13.

Testd Isevi, ellipticd, subinjlatu ; valvulls subcrassis; natibus subprominentibns ; epidermide tencbroso-fttscd:
dentibus cardinalibus subparvis erectisque ; hderalibus longis subreclisque ; margaritn alba el iridtscentr.
3

18 DESCRIITION OF MiW

Shell sinoolli, elliptical, rather iiillated; valves somewhat thick; beaks somewhat prominenl; epiilermis dark-
brown; carilinal teeth rather small and erect; lateral teeth long and nearly straight; nacre white and iriilescent.

Ilab. Abbeville District, S. C. J. P. Barratt, M, D.
My cabinet and cabinet of Dr. Barratt.
Diani. .7, Length 1, Breadtli 1.7 inches.

Shell smooth, elliptical, rather inflated, rounded before and angular behind ; substance
of the shell rather thick, thinner behind; beaks somewhat prominent, submedial; ligament
rather short and thin; epidermis dark-brown, with obscure rays, very smooth and polished;
marks of growth distant, regular and well marked; cardinal teeth rather small, compressed,
double in the left and single in the right valve; lateral teeth long, nearly straight and
enlarged at the posterior end; anterior cicatrices distinct; posterior cicatrices confluent;
dorsal cicatrices placed on the under side of the cardinal tooth; cavity of the shell rather
shallow; cavity of the beaks shallow and angular; nacre white and iridescent.

Remarks. — Dr. Barratt sent me three specimens of this species, one only being adult.
Neither of them have the beaks sufliciently |)erfect to show any undulations. In outline
it resembles U. concavus, (Nobis,) but it is more compressed, and diflers much in the colour
of the epidermis and the rays. The adult specimen is slightly salmon coloured in the
cavity of the beaks. One of the younger specimens is distinctly salmon coloured.

Ukio pvgm^us. pi. XV. Fig. 14.

TesUi Ixvi, emptied, subcompressa, struitd ; valvulis subtenuibus ; nalibus suhprominentibus ; epidermide
tenebroso-fiiscd ; dentihus curdimdibus purvia ; httendibus Uncurix szcbcurvisgue ; murguriUi cxndeii et
irideacente.

Shell smoDlh, elliptical, rather eompressed, striate; valves rather thin; beaks somewhat prominent; epidermis
dark-brown; cardinal teeth small; lateral teeth linear and slightly curved; nacre bluish and iridescent.

Hab. Abbeville District, S. C. J. P. Barratt, M. D.
My cabinet.
Diam. .4, Length .7, Breadth 1.2 inches.

Shell smooth, elliptical, rather compressed, striate, rounded before and angular behind;
substance of the shell rather thin, thicker before; beaks somewhat prominent; ligament
short and thin; epidermis dark-brown, striate, with obscure rays, and slightly polished;
umbonial slope angular; marks of growth indistinct; cardinal teeth small, compressed;
lateral teeth rather long, linear, slightly curved, and thickened at the posterior end ;
anterior cicatrices distinct; posterior cicatrices confluent; dorsal cicatrices in the centre
of the cavity of the beaks; cavity of the shell shallow; cavity of the beaks small and
angular; nacre blue and very iridescent behind.

Remarks. — This is a very small species, and a single valve only, (the right) has been
received by me. I do not think this is quite adult. The beak is not sufficiently perfect
to observe any undulations. This shell is about the size of U. fahalis, (Nobis,) and
parvus, Barnes, but cannot be confounded with either of them. It is a thinner shell than
the former and less inflated than the latter.

FRE^SH WATEII AND LAND SHKLI.S. 19

Unio fraternus. pi. XVI. Fi<r. 15.

Testa Ixvi, e/fiplicd, rnmpressii, striata, vulde ineqiiilafera/i, postice snblnans^tihiri; vahnilis SKbcrassis ;
natibus promiaulis : cpidirmide tmebroso-fttsca ; dcntibus cardiiialibus parvis, tuberculalis, striatis ; lutcrali-
bus prselongis subcnrvisqur ; margaritd vel albci v el purpurea et iridescenle.

Shell smoolh, elliptical, compressed, striate, very inequilateral, siibbiaiigular behind; valves rather thick;
beaks somewhat prominent; epidermis dark-brown; cardinal teeth small, luberculate, striate; lateral teeth very
lon^ and somewhat curved; nacre white or purple and iridescent.

Hab. Columbus, Georgia, Dr. Boykin ; Abbeville District, S. C, J. P. Barratt, M. D.
My cabinet and cabinet of Dr. Barratt.
Diam. .6, Length 1.3, Breadth 1.4 inches.

Shell smooth, elliptical, compressed, striate, very inequilateral, subbiangular behind,
obtusely rounded before, flattened on the sides; substance of the shell somewhat thick,
thinner behind; beaks somewhat prominent and placed near to the anterior margin;
ligament long and rather thick; epidermis very dark-brown, darker on the posterior slope,
with distant marks of growth; posterior slope compressed, with fold-like wrinkles, and
raised into a carina; umbonial slope obtusely angular; cardinal teeth small, tuberculate
and striate; lateral teeth very long, somewhat curved, thicker at the posterior end and
separated from the cardinal tooth; anterior cicatrices distinct; posterior cicatrices con-
fluent; dorsal cicatrices placed in a row on the interior of the plate; palleal cicatri.v
impressed; cavity of the shell very shallow; cavity of the beaks very shallow and rounded;
nacre white or purple and iridescent.

Remarks. — This species belongs to the group of which U. complainilns is the type. It
is closely allied to U. Hopctonensis, (Nobis,) but differs in being more elliptical in the out-
line, and having a less elevated carina, and in the c&rdinal teeth, which are not compressed.
The outline is more that of Vnio HcmhcU, Con., but it is not so thick a shell, and does
not possess the coarse folds on the posterior slope, which in that species distinguish it so
well. The HembcH is also darker, the strice coarser, and the umbonial slope more rounded.
Of the six specimens before me, two are white, three purple, and one slightly salmon
coloured. The margin is broad and dark coloured.

Unio Cuvierianus. PI. XVI. Fig. 16.

Testa Isevi, eliipticd, conveicd, inequilaterali, poslice obtuse angulald; vuhulis crassis ; natibus prominvlis}
epidermide nitidd, castaneo-fusrd ; dentibus cardinuUbus magnis crenuhttisque ; lalera/ibus praslongis sub-
curvisque; margaritd arg^nted.

Shell smooth, elliptical, convfex, inequilateral, obtusely angular behind; valves thick; beaks a little prominent;
epidermis shining, chestnut-brown; cardinal teeth large, crenulate; lateral teeth very long and somewhat curved;
nacre silvery white.

Hab. Washington county, Georgia, Rev, G. White.
Cabinet of Major Le Conte.
Diam. 1.5, Length 2.2, Breadth 3.9 inches.

Shell smooth, elliptical, convex, inequilateral, obtusely angular behind, inflated over the
umbones; substance of the shell very thick; beaks but slightly prominent and submodiiil;

•,*() DESCRIPTION OF NEW

ligament not very long antl moderately thick; epidermis chestnut-brown, with very
distant marks of growth; posterior slope wide, rather flattened, with two raised lines
passing from the beaks to the posterior margin; umbonial slope large and rounded;
cardinal tectii large, crenulate, double in the left and single in the right valve; lateral
teeth very long, somewhat curved and thickened towards the posterior end, separated
from the cardinal tooth; anterior cicatrices large and distinct; posterior cicatrices large
and distinct; dorsal cicatrices small, and placed nearly in the centre of the beaks; palleal
cicatrix deeply impressed; cavity of the shell wide, not very deep; cavity of the beaks
exceedingly small and rounded; nacre silvery white.

Remarks. — A single specimen only of this fine shell has come under my notice, and it
belongs to the cabinet of my friend Major Le Conte. It is a member of that great group of
which V. complanatus is the type, but it differs from that species somewhat in outline, in
being inflated over the umbonial slope, and in having a smoother epidermis.

I dedicate this fine species to the memory of the great zoologist. Baron Cuvier.

Unio Forbesianus. pi. XVL Fig. 17.

Tentn livvi, triangulari, subcompressd, inequilaterali, postice angulata; valvulis suhcruHHis ; nulihus mib-
jiroininentibua, ad apices itndiduln; epidcrmidc caalaneo-fuscd; dciitibiis cardlnulibus acuminatis, subgrundibus;
laleralibus longis subreclisque; margarila vel ulbii vel purpurea ct iridcsccnlc.

Shell smoolh, triangular, rather compressed, inequilateral, angular behind, valves rather thick; beaks rather
prominent, undulated at the tip; epidermis chestnut-brown; cardinal teeth rather large and pointed; lateral teeth
large and nearly straight; nacre while or purple and iridescent.

Hab. Savannah River. Major Le Conte.

My cabinet and cabinet of Major Le Conte.
Diam. .8, Length 1.2, Breadth 1.8 inches.

Shell smooth, triangular, rather compressed, inequilateral, acutely angular behind,
.slightly flattened before the umbonial slope; substance of the shell rather thick, thinner
behind; beaks rather prominent and rather coarsely undulated at the tip; ligament rathei
short and moderately thick ; epidermis chestnut-brown, lines of growth distant and dis-
tinct, sometimes rayed; umbonial slope raised into rather an acute angle; posterior slope
flattened and furnished with numerous angular crumpled folds; cardinal teeth rather large,
])ointed and crenulate; lateral teeth long and nearly straight; anterior cicatrices distinct;
posterior cicatrices distinct; dorsal cicatrices placed on the under side of the cardinal
teeth; cavity of the shell rather small and rounded; cavity of the beaks shallow and
angular ; nacre white or purple and iridescent.

Remarks. — Several of these of different ages, were given to me by my friend Major
Le Conte, to whom 1 owe the possession of so many new species. It is allied to U. incras-
salus, (Nobis,) but is not so transverse. In the young, the epidermis is rather polished,
and some of them have greenish rays over the middle of the disk. The smallest of them
all is purple in the nacre and beautifully iridescent. Some of the specimens seem to be
devoid of rays altogether.

Named in honour of Professor E. J'orbes, of King's College, London.

SZ. . 4n.. .^/l/.-M- :'<MrJU'/^jy/^:

|r>'r

I.'t /'/no frafrrnux.
/// .. f 'ill (rft/ifiifs.

17 ., I'\lffKWf/£tUfS.

FRESH WATER AND LAND SHELLS. 21

Unio Kleinianus. PL XVII. Fig. 18.

Testa pUcali'i, (riiinifnlari, cotnprrssci, ad hi/ere planulutfi, inaeqinlaterfili, poslice obtuse ungiihila ; valvulis
subcrassh : ntilibus subprominenlibus ; epiclennide tencbroso-fuscii ; dentibus cardinalibus crassia crcmitatis-
fjiic; laterulibus brevis reclisgue; margaritd alba el Iridescenle.

Shell plicate, triangular, compressed, flattened on the side, inequilateral, obtusely angular behind; valves rather
thick; beaks somewhat prominent; epidermis dark-brown; cardinal teeth thick and crenulate; lateral teeth short
and straight; nacre white and iridescent.

Hab. Suwanee river, Florida, Major Lc Conte.

My cabinet and cabinet of Major Le Conte.
Diam. .8, Length 1.2, Breadth 1.6 inches.

Shell plicate, triangular, compressed, flattened at the side, inequilateral, obtusely an-
gular behind, enlarged over the uinbonial slope; substance of the shell rather thick, thinner
behind; beaks somewhat prominent; epidermis dark-brown, with marks of growth rather
distant; ligament short and thick; folds irregular, small and extending nearly over the
whole disk, on the posterior slope more regular and nearly parallel; posterior slope large,
and raised into a carina, umbonial slope obtusely angular; cardinal teeth thick, large,
crenulate and double in both valves; lateral teeth short and straight, separated from the
cardinal tooth by a rather large plate; anterior cicatrices distinct; posterior cicatrices
distinct; palleal cicatrix well impressed; cavity of the shell rather deep and rounded;
cavity of the beak deep and acutely angular; nacre white and iridescent.

Remarks. — A new plicate species is rather a rare acquisition, and I believe this is the
first from Florida. Major Le Conte, I believe, procured but two specimens, both of which
are before me. In outline and size it is allied to U. infucaltis, Con., which, however, is
not figured as a folded shell by him. It differs, however, in having larger folds, which
are more interrupted, and in the colour of the epidermis, which, in infucaltis, when old, is
almost, if not quite, black. The folds in Kleinianus are very irregular, and so much
broken up as to have the appearance, on part of the disk, of being nodules. The beaks,
'unfortunately, of the two specimens are much eroded, and their characters, therefore, not
known. I should suppose that, in perfect or young specimens, the folds would extend to
the apex, and present a fine appearance.

This interesting species I dedicate to Klein, the author of Teslamen Mclliodi, 1773, who
was in advance of most of the conchologists of his day.

Unio satur. PI. XVIL Fig. 19.

Testa lasvi, Irian gulari, valdi injlata, insequilaterali, postice truncald; valvulis crassis; natibits maximis,
iijlatis, rotundatis; epidermide tenebroso-fuscd, polild ; dentibus cardinalibus magnis, compressis, obtiijuis,
uc.uminalis ; crennlatis ; laterulibus longis, lamellutis subcurvisque; margaritd albd et iridtscente.

Shell smooth, triangular, very much inflated, inequilateral, truncate behind ; valves thick ; beaks large, inflated
and rounded; epidermis dark-brown, polished; cardinal teeth large, compressed, oblique, acuminate, crenulate;
lateral teeth long, lamellar and curved ; nacre white and iridescent.

Ilab. Alexandria, Louisiana, J. Hale, M. D. Lake Calcashue, near New Orleans,
Mr. Anthony.

My cabinet and cabinets of Dr. Ilalc and Mr. Anthony.
Diam. 2.1, Length 2.5, Breadth 3 inches.

22 DESCRIPTION OF NEW

Shell smooth, triangular, very much inflated, inequilateral, truncate behind; substance
of the shell thick, beaks large, inflated, rounded and placed towards the anterior margin;
ligament short and very thick; epidermis dark-brown, polished, striate, in the young
nearly olive; lines of growth very distant; posterior slope flattened, with an obscure,
impressed, rather wide groove from the beaks to the margin; umbonial slope angular
towards the beaks and inflated; cardinal teeth large, compressed, oblique, acuminate and
crenulate; lateral teeth long, lamellar, curved, enlarged at the posterior end and separated
from the cardinal tooth; anterior cicatrices distinct; posterior cicatrices confluent, dorsal
cicatrices placed on the under side and near the edge of the plate; palleal cicatrices not
deeply impressed; cavity of the shell very deep and rounded; cavity of the beaks very
deep and rounded ; nacre white and iridescent.

Remarks. — Several specimens of this species have been in my possession for some
years. It belongs to the group of which U. ovatus, Say, may be considered the type. It
is more like U. occidens, (Nobis,) than ovahis, having the umbonial slope rounded. It
diflers, however, from the latter species in having a more inflated disk, and in being darker
and rounder. It is not so inflated as capax. Green, but much like it. All the five indi-
viduals before me are females, unless the youngest one. The truncation of the posterior
margin is very remarkable. In the oldest specimen, that portion of the disk is so turned
in, as to present nearly a flat surface. The beaks are very much inflated and drawn
back.

Unio Lamarckianus. pi. XVII. Fig. 20.

Testa nodulosd, subrotunda, comprcssa, in medio planulata, subequilaterali, posliee subangulatd, pi(ncti-
imeuliis pns.sim radlald; ^'a!vu/is crassis ; natibl(s prornlnenlibus, compressis, ad apices iinduhilis ; epidermide
luted, virido-radiutu ; rudiin numerosis interrujHis ; denlibits cardinalibus magnis, comprcssis ; latcralibus
brevibus crassisgue ; margarita argented.

Sliell nodulose, subrotund, compressed, flattened in the middle, nearly equilateral, obtusely angular behind,
with dotted rays over the whole disk; valves thick; beaks prominent, compressed, and angular at the point;
epidermis yellow, with green rays ; rays numerous and interrupted ; cardinal teeth large, compressed ; lateral
teeth short and thick ; nacre silvery white.

Hab. Caddo river, Arkansas, Professor Powell. Washitta river, near the Hot Springs,
Arkansas, Dr. Hale.

My cabinet and cabinets of Prof. Powell and Mr. Shaefier.
Diam. .5, Length 1.1, Breadth 1.4 inches.

Shell nodulous, subrotund, compressed, flattened from the beak to the basal margin,
nearly equilateral, obtusely angular behind, with dotted rays over the whole disk; sub-
stance of the shell thinner behind; beaks prominent, compressed and angular at the
point; ligament very short and thick; epidermis yellow, with green rays over the whole
disk, on the anterior part furnished with a few larger rays; lines of growth distant; rays
numerous, interrupted, dotted and chain-like; umbonial slope raised into an obtusely an-
gular ridge from the beaks to the posterior basal margin; cardinal teeth large, compressed,
crenulate; lateral teeth short, thick and enlarged at the posterior end; anterior cicatrices
distinct; posterior cicatrices distinct, dorsal cicatrices small and placed on the under side

,%Z^.. I, iM,/.iC.fA%f.-^flJ/a^/^

fei .. j

.y

IS Unio ^einitinus.

i9 satar.

70 „ /, fitn arfA'fait us.

FRESH WATER AND LAND SHELLS. 23

of tlie cardinal tooth; pallcal cicatrices impressed; cavity of the shell very shallow; cavity
of the beaks rather deep and angular; nacre silvery white.

Remarks. — The curious and beautiful interrupted rays which cover the whole disk of
this species, bring it into the group of which the U. irroratus, (Nobis,) was the first
described, and may be considered the type. There are now four known, all of which, while
easily distinguished, have very much the same general characteristics, — irroratus, dromas,
capcralus and Lamarckianus. The five specimens before me are of diflerent sizes. The
largest is the most perfect one, and is that which is figured. It is about the size of a
young dromas, when about to finish its two humps. It differs from all the other three
species, in having an angular ridge from the beaks to the posterior basal margin. The
beaks are remarkably compressed and pointed, like securis, (Nobis.) The nodules arc
little more than rugosities, disposed to run into small folds. Both this and caperalus
might be said scarcely to belong to the nodulous division of the genus, but they are cer-
tainly not devoid of nodules, though they are small and irregular. The lines of growth
are very different from caperalus. In the latter they are very close. In outline, the
Lumarckiamis is nearly the same with intermedins. Con., from Tennessee. It cannot,
however, be confounded with that species, as it has not the furrow which that shell has
on the posterior slope; nor has it the well expressed verrucosc character of it. It differs
also in the rays, which in intermedias are arrow-head shaped. Indeed the intcrmcdius
belongs to another group, of which metanever, Raf., may be considered the type.

I dedicate this beautiful species to the memory of the great naturalist Lamarck.

Uniohebes. pi. XVIII. Fig. 21.

Testa Ixvi, ol)ton2;i't, subcnnipressi'i, ad latere plamdatd, iniequUaternli, postice tnmcalu; vatvulis stilicrassis;
nalibus subprominentibus, ad apices undutatis; epidermide striata tenebroso-fuscd, eradiatii ; denlibus cardi-
nutibus subcrassis, compressis, obtiquis, acuminatis ; lateralibus tongis ctirvisqtie ; margaritd alba.

Shell smooth, oblong, rather compressed, flattened on the side, inequilateral, truncate behind; valves rather
thick; beaks somewhat prominent, Undulate at the tip; epidermis striate, dark-brown, rayless; cardinal teetli
rather thick, compressed, oblique, acuminate ; lateral teeth long and curved ; nacre white.

Hab. Oconee river, near Athens, Georgia. Major Le Conte.
My cabinet and cabinet of Major Le Conte.
Diam. .8, Length L3, Breadth 2.2 inches.

Shell smooth, oblong, rather compressed, flattened on the side, inequilateral, truncate
behind, rounded before; substance of the shell rather thick, beaks somewhat prominent,
undulated at the tip and submedial; ligament rather long, thin and nearly covered; epider-
mis dark brown, without rays, thickly striate over the lower half of the shell, thick and
smooth above; lines of growth not well defined; posterior slope compressed into an
elevated carina, with a slightly impressed furrow, which has two very obscure raised lines;
umbonial slope rounded ; cardinal teeth rather thick, compressed, oblique, acuminate,
crenulate and double in both valves; lateral teeth long, curved and thickened at the pos-
terior end; anterior cicatrices distinct; posterior cicatrices confluent; dorsal cicatrices
placed nearly in the centre of the cavity of the beaks; cavity of the shell shallow and
wide ; cavity of the beaks shallow and obtusely angular ; nacro white.

21 BESCRIPTION OF NEW

Remarks. Amonir the many shells from Georgia which I owe to the kindness of Major

Le Conte, was a single specimen of this species. It is allied to U. Lccoiifiamis, (Nobis,)
and is like it in outline; but it is more compressed, higher in the carina, and much more
striate and rough on the exterior; it is also a thinner shell. The posterior margin of this
specimen is also slightly emarginate. The tips of the beaks are not perfect, but they arc
enou<Th so in this specimen, to show that the undulations are more numerous than usual
and very beautiful. The upper portion of the double lateral tooth is very small in this
specimen.

Unio Moussonianus. pi. XVIII. Fig. 22.

Testa Ixvi, elliptica, subconvexa, subinegiiilaterali, poslice angulalA; valvuiis prrcrassls ; nal thus promt-
ncntUnis, crtmsin ; tp'tdcnnide castaneo-fusa'i ; dentibus cardinttlibun magnis, mtbcotnprcssis ; luleruUbus
lungh, crasain subciirviitiis ; margurild argcnted el iridescenle.

Shell smooth, elliptical, subeonvex, subinequilateral, angular before; valves very thick; beaks prominent and
thick; epidermis cbcslniit-browii ; cardinal teeth large, rather compressed ; lateral teeth long, thick, somewhat
curved ; nacre silvery while and iridescent.

Hab. Georgia, J. P. Barratt, M. D.

My cabinet and cabinet of Dr. Barratt.
Diam. 1.1, Length 1.8, Breadth 2.8 inches.

Shell smooth, elliptical, subconve.v, somewhat inequilateral, angular behind and rounded
before; substance of the shell very thick, rather thinner behind ; beaks prominent and
thick; ligament rather long and thick; epidermis chestnut-brown, marks of growth distant
and rather distinct ;umbonial slope obtusely angular; cardinal teeth large, rather compressed,
double in the left and single in the right valve; lateral teeth long, thick, laminate, thick-
ened towards the posterior end and slightly arched; anterior cicatrices distinct; posterior
cicatrices distinct ; dorsal cicatrices placed on the under side of the plate, near to the
edge ; palleal cicatri.\ impressed ; cavity of the shell not very deep ; cavity of the beaks
rather shallow and angular ; nacre silvery white and iridescent.

Remarks. — The outline and general appearance of this species reminds one of U. dclo-
dontus. Lam. It is, however, a thicker shell and has thicker teeth. But three specimens
were received by me. One of them is slightly tinged with salmon colour in the cavity
of the beaks, and others may be found very likely more deeply coloured.

I dedicate this species to Prof. A. Mousson, of Zurich, the author of " The Land and
Fresh Water Shells of Java."

Unio nigerrimus. PI. XVIII. Fig. 23.

Tesl/i lasvi, elliptic(i, siibconvext'i, inxqiiilaferaUfposlice subroUindutA; vaividis siibtenuibiis} nutibiis jmrvis,
promimdis, ad apices nndtthitis; epidermlde nigra, nitidci, striata; dentibus cardinalibus siibcompressis,
oblifjuis, acuminalis, cremtlalis; lateralibus longis, lamellatis subcurvisque; margaritd ulhd et valde iridescente.

Shell smooth, elliptical, rather convex, inequilateral, rounded behind; valves rather tiiin ; beaks small, slighdy
prominent, undulated at the tip ; epidermis black, shining, striate ; cardinal tectli raliier compressed, oblique,
acuminate, crenulate ; lateral teeUi long, lamellar and somewhat curved ; nacre white and very iridescent.

.^^ ,^.^. .^ .S^ 3f^.%^o/'A:^/&

EJ

^3

'*'* . .Vf/rissofuatttis
1V» - nv/erTtnitt.y

FRESH WATER AND LAND SHELLS. 25

Hab. Alexandria, Louisiana, J. Hale, M. D.

My cabinet and cabinets of Dr. Hale, and Acad, of Nat. Science.
Diam. .7, ' Length L3, Breadth 2.2 inches.

Shell smooth, elliptical, rather convex, inequilateral, rounded behind; substance of the
shell rather thin; beaks small, slightly prominent, undulated at the tip; ligament rather
long and thin; epidermis shining, black, striate, in the young radiate all over the disk;
marks of growth rather distant; posterior slope compressed into a small carina; umbonial
slope slightly raised and rounded ; cardinal teeth rather large, somewhat compressed,
oblique, acuminate, crenulate and double in both valves; lateral teeth long, lamellar, some-
what curved and separated from the cardinal tooth; anterior cicatrices distinct; posterior
cicatrices confluent; dorsal cicatrices placed near the edge of the plate and on the car-
dinal tooth; cavity of the shell rather shallow; cavity of the beaks shallow and subrotund;
nacre white and very iridescent.

Remarks. — This species is nearly allied to U. Haleiamis, (Nobis.) but differs in the
outline, and is not so wide; in the epidermis, which is blacker and more shining, and in
the beaks, the undulations of which are more numerous and less regular. It belongs to
that group of which U. Nnshvilliamis, (Nobis,) may be considered the type, the beaks being
very much, in their undulations, of the character of that species. All the adults, male
and female, of which I have many specimens, are very black and apparently without rays,
but when held up to a strong light, delicate obscure rays may be observed, particularly
about the umbonial slope. In the individuals of one-third growth and less, the epidermis
is dark-green and covered with rays. The female differs very much in outline from the
male, and is much inflated on that portion of the disk which tends to the posterior l)asal
margin. In this very much enlarged female characteristic, this species resembles Nas/t-
viUianus, Halcianus and parvus. This enlargement makes that margin obliquely truncate.

Unio Prevostianus. PI. XIX. Fig. 21.

Testa Isevi, ellipticd, subcompressd, valde inequilaterali, postice rotundulu ; vafvuli.i pertenuibus; nntibun
partus, prominulis, ad apices tindulatis ; epiclerinide luted, tenehroso-radiald, polita ; dentibus caritinaJibus
parvissimus, cotnpressis, perobliquis ; lateralibus longis, lamellutis subcurvisque ; marguritd ca;ni/ed el
iridescente.

Shell smooth, elliptical, rather compressed, very inequilateral, rounded behind; valves very tliin ; beaks small,
slightly prominent, undulated at the lip; epidermis yellow, very much and darkly radiated, polished; cardinal
teeth very small, compressed, very oblique; lateral teeth long, lamellar and somewhat curved; nacre bluish and
iridescent.

Hab. Eutowah River, Georgia, Mr. C. M. Wheatley.
Cabinet of Mr. Wheatley.
Diam. .7, Length 1.2, Breadth 2.3 inches.

Shell smooth, elliptical, rather compressed, very inequilateral, rounded behind ; substance

of the shell very thin; beaks small, slightly prominent, undulated at the tip; ligament lonnr

and ihin; epidermis polished, yellow, with numerous broad dark-green ra^'s covcrinnr

nearly the whole disk, lighter before and very dark behind, with very distant marks of

4

26 DESCRIPTION OF NEW

growth ; posterior slope compressed and raised into a carina and very dark-green ; um-
honial slope bnt sliglitly raised and rounded ; cardinal teeth very small, compressed, very
oblique, double in both valves; lateral teeth long, lamellar, somewhat curved and abrupt
at the posterior end, separated from the cardinal tooth; anterior cicati ices distinct; pos-
terior cicatrices confluent; dorsal cicatrices placed in the cavity of the beaks and on the
under side of the plate; palleal cicatrices very indistinct ; cavity of the shell rather shal-
low and rounded; cavity of the beaks shallow and subangular; nacre bluish and beauti-
full}' iridescent.

Remarks. — A single specimen only was received by Mr. Wheatley from Georgia. In
outline it is very much the same as U. radiah/s, but it is a much thinner shell, and in its
polish, rays, and thinness allied to U. Modioliformis, (Nobis.) The rays in this specimen
are so numerous, broad and dark, as to give the shell quite a tenebrose appearance, almost
obliterating the ycllowishness of the epidermis.

I name this species after Professor Prevost of Geneva, who, in his able memoir, "De la
generation chez les monies des peintres" (Unio piclorum) was the first by anatomical de-
monstration to prove the Naiades to be dioecious; it having been previously supposed the
male and female organization existed in the same individual. (See Mem. de la Soc. dc
I'Hist. Nat. de Geneve, March 17, 1825.)

Unio PowELLii. PI. XIX. Fig. 25.

Testa Ixvi, elliplicd, subinjlata, insequilaterali, postice angtilald; valvuUs suhtemiibuH ; nutibus sidr/jromi-
nentlbus; cpidcrmide oHvaccn,}}ilidd, crad'mta ; dcntibvs cardvudibus parvis, sitbcompressis, obliqids, (tciinii-
nalis; lateralibus prselongis siibcurvisque ; margaritd albd ct iridcscenle.

Shell smooth, elliptical, somewhat inflated, inequilateral, angular behind; valves rather thin; beaks rather
prominent; epidermis olivaceous, shining, without rays; cardinal teeth small, rather compressed, oblique, acumi-
nate; lateral teeth very long and somewhat curved; nacre white and iridescent.

Hab. Saline river, Arkansas, J. Hale, M. D., and Professor Powell.
My cabinet and cabinets of Dr. Hale and Prof. Powell.
Diam. 1.1, Length 1.8, Breadth 3.1 inches.

Shell smooth, elliptical, somewhat inflated, inequilateral, angular behind; substance of
the shell rather thin, thicker before; beaks rather prominent and placed towards the
anterior margin; ligament long and rather thick; epidermis olivaceous, shining, without
rays, with distant, indistinct marks of growth; posterior slope rather depressed, with two
slightly impressed lines from the beaks to the posterior margin; umbonial slope sub-
angular; cardinal teeth small, rather compressed, oblique, pointed, crenulate, single in the
right and double in the left valve; lateral teeth very long, somewhat lamellar, curved,
separated from the cardinal tooth; anterior cicatrices distinct; posterior cicatrices con-
fluent; dorsal cicatrices placed on the under side of the plate between the teeth; palleal
cicatrices impressed; cavity of the shell rather deep; cavity of beaks deep and obtusely
angular; nacre white and iridescent.

Remarks. — I owe to the kindness of Dr. Hale and Prof. Powell several specimens of
this species of both se.ves. It belongs to that group of which cariosus, Say, may be con-

#

.^ly. . ^../.'^^^< ^.'64;^.'';^/'^'.^//^

h-

.-t_...i

3^

ii^

1*-/ ^7///> rrevos(tfi/tiix
2ft . af'/'ftus

FRESH WATER AND LAND SHELLS. 27

sidcred the type. In its outline it approaches the luleohis, Lam., but is not quite so trans-
verse, while it is more so than cariosus. Two of the specimens are richly salmon-coloured
in the cavity of the shell — the others are all white. The females are very much enlarged
over the umbonial slope, and expanded at the posterior basal margin. None of the speci-
mens which I received have any rays.

I have named this species in honour of Prof. W. Byrd Powell, of Memphis, Tcnn.

Unio affinis. pi. XIX. Fig. 26.

Testa Isevi, eUiptica, convcxu, inequilaterali, postice rotundata ; vidvulis subtenuibiis; natibus suhpromi-
nentibus; epidermide radiatd, luteola, nitidd; dentibus cardinalibus parvis, compres.iis, obliquis, acurninalis,
crenuhilis ; laleralibus sublongis, lameUatis subcurvisque ; margarila alba et iridescenlc.

Shell smooth, elliptical, convex, inequilateral, rounded behind; valves rather thin; beaks rather prominent,
epidermis rayed, yellowish, shining; cardinal teeth small, compressed, oblique, acuminate, crenulale; lateral
teeth rather long, lamellar and rather curved; nacre white and iridescent.

Hab. Alexandria, Louisiana, J. Hale, M. D.

My cabinet.
Diam. .9, Length L4, Breadth 2.1 inches.

Shell smooth, elliptical, convex, inequilateral, rounded behind and inflated over the
umbones; substance of the shell rather thin; beaks rather prominent, placed towards the
anterior margin; ligament rather short and somewhat thick; epidermis shinrng, yellowish,
with numerous rays and rather distant marks of growth; posterior slope rather elevated;
umbonial slope rounded and inflated; cardinal teeth small, compressed, oblique, acuminate,
crenulate, double in both valves; lateral teeth rather long, lamellar, slightly curved,
separated from the cardinal tooth; anterior cicatrices distinct; posterior cicatrices con-
fluent; dorsal cicatrices placed across the cavity of the beak under the cardinal tooth;
cavity of the shell rather deep and rounded; cavity of the beaks rather shallow and sub-
angular; nacre white and iridescent.

Remarks. — The outline of the specimen before me is of a remarkably regular oval. It
belongs to the group of which cariosus. Say, may be considered the type. It is nearest in
general character to U. crocalus, (Nobis,) but it is a larger species, not angular behind,
and the rays are broader.

Unio proximus. PI. XX. Fig. 27.

Tesid Ixvi, el/ipficd, subinjfafd, siibinxqidJuterali, posliee rohindiitd: valvu/is lennibiis ; nalilnm parvi.s,
sitbprominentibus ; epidermide luted, radiatd; dentibus cardinalibus valde compressis, obliquis, acurninalis;
lateralibus longis, lamellalis subreclisque; margaritd alba et iridescente.

Shell smooth, elliptical, somewhat inflated, subinequilateral, rounded behind; valves thin; beaks small, some-
what prominent; ejiidermis yellowish, radiated; cardinal teeth much compressed, oblique, acuminate; lateral
teeth long, lamellar and nearly straight; nacre white and iridescent.

Hab. Georgia. J. P. Barratt, M. D.

My cabinet and cabinet of Dr. Barratt.
Diam. .7, Length 1.2, Breadth 2.1 inches.

38 DliSCRIPTlOiN OF NEW

Shell smooth, elliptical, somewhat inflated, rather inequilateral, rounded behind; sub-
stance of the shell thin; beaks small, slightly prominent; ligament rather short and thin;
epidermis yellowish, with rather small, somewhat distant rays on the posterior portion of
the disk, and with strong distant marks of growth; posterior slope rather depressed;
umbonial slope gradually rounded; cardinal teeth much compressed, oblique, acuminate,
double in both valves; lateral teeth thin, rather long, lamellar, nearly straight and sepa-
rated from the cardinal teeth; anterior cicatrices distinct; posterior cicatrices confluent;
dorsal cicatrices placed rather below the centre of the cavity of the beaks; palleal cica-
trix impressed anteriorly; cavity of the shell rather deep; cavity of the beaks rounded;
nacre white and iridescent.

Remarks. — I have before me but a single specimen of this shell, and with older, younger
or more perfect specimens, the characters are very likely to vary. In nearly all its cha-
racters it is most nearly allied to U. ohsciirus, (Nobis.) It differs in being less angular at
the posterior margin, in being a thinner shell, and in having the teeth lamellar and thin.
The colour of this specimen is white, while the obscurus is usually partly purplish.

Unio Reeveianus. pi. XX. Fig. 28.

Testa Ixvi, el/iptlra, injfa/d, valde inequilateraU, poslice obiuso-angulula ; vahxilis lemdbus; natibus parvis,
promimilis : rpidernnde lutea, radiatu ; dentibua cardiiialibus parvis, Hubobluiuin ; lateralibus longh, temd-
bua subcurvhqup; margarifii alba et iridescente.

Shell smooth, elliptical, inflated, very inequilateral, obtusely angular behind; valves thin; beaks small, a little
prominent; epidermis yellowish, radiated; cardinal teeth small, rather oblique; lateral teeth long, thin and curved;
nacre white and iridescent.

Ilab. Alexandria, Louisiana, J. Hale, M. D., and Prof. Powell.
INIy cabinet and cabinets of Dr. Hale and Prof. Powell.
Diam. 1.1, Length 1.6, Breadth 2.9 inches.

Shell smooth, elliptical, inflated, very inequilateral, obtusely angular behind; substance
of the shell thin, thicker before; beaks small and a little prominent; ligament rather long
and somewhat thfck; epidermis yellowish, shining, with numerous green rays over the
posterior portion of the shell and distant lines of growth; posterior slope rather com-
pressed into a carina; umbonial slope but slightly raised and rounded; cardinal teeth small,
rather oblique, double in the right and slightly double in the left valve; lateral teeth long,
thin, somewhat curved, widely separated from the cardinal teeth; anterior cicatrices dis-
tinct; posterior cicatrices confluent; dorsal cicatrices placed on the under side of the
plate; palleal cicatrix impressed; cavity of the shell deep; cavity of the beaks rather shal-
low and subangular; nacre white and iridescent.

Remarks. — Among the many interesting shells sent to me by Dr. Hale and Prof. Powell,
were two specimens which are now before me. The larger one, which is here figured, is
apparently a male, the other a female. They differ much, the latter being much smaller,
but apparently grown. It is very much broader on the posterior portion, and somewhat
truncate. In colour and form of ra3's the two specimens are the same. Neither of them
are by any means perfect, being much eroded towards the beaks, the character of which,

Ji:^U^JmM./'^-<r^^M 10^^ f^

r^

4

Zi

27 Vhxo proxiTitus
'ZS . ffe^rcfUiuzs

'19 . luridxis

Frtim J'i\tlurr ly /bhoffitii

FRESH WATER AND LAND SHELLS. 29

in regard to undulations, cannot be ascertained. In general outline and characteristics,
it is allied to U. luteoliis. Lam. It is, however, thinner and lighter in the substance of
the shell, and the rays are not so broad. The teeth, too, are smaller, and the lateral are
much more removed from the cardinal ones. In the two specimens before me the division
of the lateral teeth is remarkably short, not reaching more than half the length of the
tooth.

I dedicate this species to Lovell Reeve, Esq., the able author of " Conchologia
Iconica."

Unio LURiDUS. PI. XX. Fig. 29.

Testa Isevi, elliptica, compressa, vulde inxquilateruli, postice siibbiangidatd ; valvulls subcrassis; natibus
parvis, vix prominulis ; epidermide tenebrosobruned, striata, eradiala; denlibus cardinalibus parvia, acumi-
nalis; lateriilibus longis curvisque ; margaritd vel cseruled-albd vel salmonis colore llnctd.

Shell smooth, elliptical, compressed, very inequilateral, subbiangular behind; valves somewhat thick ; beaks
small, scarcely prominent; epidermis dark-brown, striate, without rays; cardinal teeth small, acuminate; lateral
teeth long and curved; nacre bluish-white or salmon-coloured.

Hab. Coosawattee river, Murray county, Georgia, Dr. Boykin.
My cabinet.
Diam. .6, Length 1, Breadth 2 inches.

Shell smooth, elliptical, compressed, very inequilateral, subbiangular behind; substance
of the shell somewhat thick; beaks small, scarcely prominent, placed towards the anterior
margin; ligament rather long and thin; epidermis dark-brown, striate, without any appa-
rent rays, with rather distant marks of growth; posterior slope rather compressed; um-
bonial slope very slightly raised into a scarcely visible angle; cardinal teeth small, acumi-
nate, double in the left and single in the right valve; lateral teeth long, curved and
enlarged at the posterior end; anterior cicatrices distinct; posterior cicatrices confluent;
dorsal cicatrices placed above the centre of the cavity of the beaks; palleal cicatrices
slightly impressed; cavity of the shell very shallow; cavity of the beaks exceedingly shal-
low and rounded ; nacre bluish-white and salmon coloured.

Remarks. — Some half dozen of this small, unattractive species I owe to the kindness of
my late friend, Dr. Boykin. Two of them are slightly salmon coloured, the others are
bluish-white. It is somewhat like V, complanalus ; but, in outline, it is more like occullus,
(Nobis,) the beak is more terminal than in either, and the whole appearance of the shell
reminds one of U. ardlor, (Nobis,) but it is not so wide a shell. Several of the speci-
mens are not so dark a brown as the others, but are inclined to dark-olive.

Unio Clarkianus. PI. XXI. Fig. 30.

Testa Isevi, elliptica, convexd, ad itmbonis injlutd, incquilaterali, postice angidatd; vcdviilis crassis; natibus
siibprominentibus, subrotundis: epidermide rufo-fuscd, nitidd ; dentibus cardinalibus subcrassis, acuminalis,
granulatis; lateralibus siibbrevibus, crassis, arcuatis; margaritd vel alba vel salmonis colore tinctd et
iridescente.

Shell smooth, elliptical, convex, on the umbones inflated, inequilateral, angular behind; valves ihick; beaks
rather prominent, subrotund; epidermis reddish-brown, shining; cardinal teeth rather thick, acuminate, granular;
lateral loelh rather sliort, tliirk nnd arched; nacre while or salmon coloured and iridescent.

30 DESCRIPTION OF NEW

Hab. Williamsport, Tcnn., Mr. Jos. Clark; Georgia or Alabama, Mr.C. M. Whcatlcy.
My cabinet and cabinets of Mr. Clark and Mr. Wheatley.
Diam. 1, Length 1.4, Breadth 2.2 inches.

Shell smooth, elliptical, convex, on the umbones inflated, inequilateral, angular behind;
substance of the shell thick, thinner behind ; beaks rather prominent, subrotund, submetiial ;
ligament short and thick; epidermis reddish-brown, shining, with rather close, distinct
marks of growth; posterior slope wide, and rather depressed ; umbonial slope very obtusely
angular; cardinal teeth rather thick, acuminate, granular, single in the right and double in
the left valve; lateral teeth rather short, thick, arched, thicker towards the posterior end,
separated from the cardinal teeth; anterior cicatrices distinct; posterior cicatrices con-
fluent; dorsal cicatrices placed nearly in the centre of the cavity of the beaks; cavity of
the shell deep and rounded; cavity of the beaks deep and angular; nacre white or salmon-
coloured.

Remarks. — There are two specimens before me of nearly the same size; that from
Williamsport is slightly salmon-coloured in the cavity of the shell, and has rays over
nearly the whole disk. The other has no rays whatever. This species is allied to
U. crocahts, (Nobis,) but is a larger, thicker and more regularly oval shell.

I name it in honour of my friend Mr. Joseph Clark, of Cincinnati.

Unio Floridensis. pi. XXI. Fig. 31.

Tcsld leevi, obovatd, suhlransversd. suhcompressa, vahle inxquilalerali, an/ice angusid, postlce subhild ;
valviilis terndbits; nalibus prominidis, fere terminulibus ; dcntibus cardinalibus parvis ; htleniUbus longis
nubcurviiiqiie; marguritd alba.

Shell obovate, rather wide, somewhat compressed, very inequilateral, narrow before and rather broad behind;
valves thin; beaks somewhat prominent, nearly terminal ; cardinal teelh small; lateral teelh long and slightly
curved ; nacre while.

Hab. Chacktahachi river. West Florida, Major Le Conte.
Cabinet of Major Le Conte.
Diam. .9, Length 1.5, Breadth .3 inches.

Shell reversely ovate, transverse, rather compressed, very inequilateral, narrow before
and broad behind; substance of the shell thin, thickened before; beaks rather small and
somewhat prominent; placed near to the anterior margin; ligament long and rather thick;
epidermis light-yellow, with equal, somewhat distant lines of growth, apparently without
rays; cardinal teeth very small, lobed, double in both valves; lateral teeth very long, very
thin, and .slightly curved; anterior cicatrices distinct; posterior cicatrices confluent;
dorsal cicatrices placed in the centre of the cavity of the beaks; cavity of the shell ratiier
shallow; cavity of the beaks shallow and subangular; nacre white.

Remarks. — This is a species very distinct from any which I have seen. Its obovate
form, while it is so wide, is very unusual. It cannot be confounded with V. modioli/ormis,
(Nobis,) which is a thinner shell, rayed and much inflated. The teeth are remarkably
small, for the size of the shell, and the lateral one particularly attenuate. The epidermis
is of the yellow colour and texture peculiar to U. anadontoides, (Nobis,) and U. cariosus, Say.

%a^..4.^^:^^y^:'^ue^^ij /a^1^/:I/.

37

I

30 JTnio Clarkiojuis

31 . Floruieitsis
32

SllCCijSSHS

1 Ktttu/T hyJl-bifVan

FRESH WATER AND LAND SHELLS. 31

A single specimen only is under my inspection, and this is much eroded on the superior
portion, leaving only false beaks. It is not, of course, possible to say whether the tips
are undulate or not.

Unio succissus. pi. XXI. Fig. 32.

Testa IrVin, STcb/rianf^tilari, suhcowpressn, inxquilateruU, tcnebroso-fusca ; vuhndh suhcrassh; natilnia
subprominentibus ; dentibus cardinalibus magnis; lateralibus j^trvis subrectisque ; margarild purpurtit el
valcle iridescenle.

Shell smooth, ?ubtriangu!ar, rather compressed, inequilateral, dark-brown; valves rather thick; beaks some-
what prominent; cardinal teeth large; lateral teelh nearly straight; nacre purple and very iridescent.

Hab. West Florida, Major Le Conte.

My cabinet and cabinets of Major Le Conte and Prof. Haldeman.
Diam. .7, Length 1.2, Breadth 1.7 inches.

Shell smooth, subtriangular, rather compressed, inequilateral, subangular behind and
rounded before, subangular on the umbonial slope, dark-brown; beaks somewhat promi-
nent and placed near the anterior margin; ligament very short and rather thin ; epider-
mis dark-brown, with indistinct, rather distant lines of growth, smooth on the superior
portion, striate and rather rough towards the margin, apparently without rays; cardinal
teeth large, rather erect, double in both valves; lateral teeth rather short, thin, and very
slightly curved; anterior cicatrices distinct; posterior cicatrices distinct; dorsal cicatrices
placed on the inferior portion of the cardinal teeth, within the cavity of the beaks; cavity
of the shell rather shallow; cavity of the beaks deep and angular; nacre purple, some-
what clouded, and very iridescent.

Remarks. — A single specimen of this species was sent to me by Major Le Conte. The
beaks, being eroded, do not present the means of ascertaining if this be undulate at the
tip. The general outline approaches very closely to U. rubiginosus, (Nobis,) but it is
rather more carinate on the posterior slope, and more compressed on the anterior portion
of the shell. It differs entirely from that species in its nacre, belonging, in regard to
colour, to the complanalus group, which varies so much in purple, white and salmon. The
specimens before me are not of a deep purple, but rather pale, and clouded with white.
The margin and teeth are the darkest. In other individuals the colour may be found to
vary from dark-purple to white.*

Prof Ilaldeman's specimen is less triangular. It also came from Major Le Conte.

Unio Oregonensis. PI. XXIL Fig. 33.

to

Tesld Ixvi, elliplkd, subinjiald, subinsegmlaterali, postice obtuse angulald; valvulis crassis; nallbus sub-
prominentibus; epidermide tenebroso-olivaced, rugosdi valde striatd, obsolete radiatd; dentibus cardinalibus
magnis, obliquis, compressis et valde crenulatd; lateralibus longis, subcrassis curvutisque ; margarild utbd et
iridesccnte.

* Since the above was written, 1 have seen, in Mr. Wheatley's collection, two specimens IVom New Orleans,
both of which are white.

32 DESCRIPTION OF NEW

Shell smooth, elliptical, somewhat inflated, inequilateral, obtusely angular behind; valves thick, beaks some-
what prominent; epidermis dark-olive, rough, very much striate, obsoletely radiated ; cardinal teeth large, oblique,
compressed and much crenulated; lateral teeth long, rather thick and curved; nacre white and iridescent.

Hab. Columbia river, Oregon, Mr. C. M. Wheatley.
Diain. .8, Length 1.2, Breadth 2.1 inches.

Shell smooth, elliptical, somewhat inflated, inequilateral, obtusely angular behind; sub-
stance of the shell thick, thinner behind; beaks somewhat prominent, submedial; ligament
rather short and somewhat thick ; epidermis dark-olive, very rough, and striate over the
whole disk, with very obscure, rather thin rays; posterior slope somewhat compressed;
umbonial slope obtusely angular; cardinal teeth large, oblique, compressed and much
crenulated, double in the left and single in the right valve; lateral teeth long, rather thick,
curved, enlarged at the posterior end and separated from the cardinal tooth; anterior
cicatrices distinct; posterior cicatrices distinct; dorsal cicatrices placed obliquely on the
inner portion of the cardinal tooth and under the plate; palleal cicatrix impressed; cavity
of the shell rather shallow; cavity of the beaks shallow and subangular; nacre white and
iridescent.

Remarks. — I owe to the kindness of Mr. Wheatley one of the two specimens before
me. It is a species very distinct from any I am acquainted with. The roughness of the
exterior is remarkable, and would indicate its inhabiting near to brackish waters. It is
not usual to see a rough shell like this with rays. In those specimens which are eroded
and old, they are indistinct; but I suspect that when perfect the rays might be very dis-
tinct. In outhne, it is somewhat like a young U. Ugamentinus, Lam., {crassus, Say,) and
the nacre is of the same pure white, but the surface is totally different, being rough, and
the form more transverse. In its elliptical outline it comes closer to U. Sapotalensis,
(Nobis,) but is a smaller shell, and differs much in the rays and the surface.

Unio RuMPHiANus. PI. XXII. Fig. 34.

Testa tubermlata, quadrata, subinjlald, subinxqtnlaterali, postice truncal a, ad basim emarg;inata; valvuHs
percrussis; natihus crassis, prominentibus; epidermide rufofuscd, svbstriatd; dentibus curdinalibus percraasis
striatisgite; lateralibus brevibus rectisqiie; margaritd argented et iridescente.

Shell tuberculate, quadrate, somewhat inflated, rather inequilateral, truncate behind, emarginate at the basal
margin; valves very thick; beaks thick and prominent; epidermis reddish-brown, substriate; cardinal teeth very
thick and striate; lateral teeth short and straight; nacre silver wiiite and iridescent.

Hab. West Georgia? Dr. Budd.

Cabinet of Dr. Budd, New York.
Diam. 1.1, Length 1.7, Breadth 2 inches.

Shell tuberculate, quadrate, somewhat inflated, rather inequilateral, truncate behind,
emarginate at the basal margin, raised over the umbonial slope and grooved from beaks
to basal margin; substance of the shell very thick, thinner behind; beaks thick, submedial
and prominent; ligament short and thick; epidermis reddish-brown, somewhat striate,
with distinct, proximate marks of growth; posterior slope compressed, raised into a carina
and covered with curved rows of tubercles; umbonial slope raised into a widening ridge.

S^^uX,. lJ^.:4^4c,^!^^^^^ff.

&

,7,"J I'tiio OretfonrnsiA'
3S .. saqiiti/onntS .

fnim .lahirt l>y /hb.

FRESH WATER AND LAND SHELLS. 33

which enlarges the posterior basal margin; cardinal teeth very large, thick, spread out,
and deeply striate; lateral teeth short, thick, straight, with a large, flat plate separating
them from the cardinal teeth; anterior cicatrices distinct and deeply impressed; posterior
cicatrices confluent; dorsal cicatrices placed on the inner side of the plate; palleal cicatrix
impressed; cavity of the shell rather deep and small; cavity of the beaks very deep and
angular; nacre silvery white and iridescent.

Remarks. — A single valve only was in the collection of Dr. Budd, and he thinks it came
from the west of Georgia. I have had it in my possession for several years, and deferred
describing it in the hope of getting more specimens; but in comparing it with its allied
species, metanever, Raf, luberosiis, (Nobis,) and sparsis, (Nobis,) I have found it too dif-
ferent in outline and some other characters to place it with either. It is much more
enlarged on the posterior slope, which is almost winged, and it is without a groove on
that part, which the other three have. In this specimen the groove over the middle of the
valve is deeper than in the other species. The anterior portion is more enlarged than in
the others, and it has many rather low tubercles, the general character of which, over the
whole disk, is rather depressed and smooth. In the tiiberosiis and mctancver the tubercles
are generally more raised and roughened. The tubercles on the posterior slope in this
specimen arrange themselves in curved rows, which, running to the margin, make it
crenulate.

The lateral teeth are remarkably short, straight, and very thick. The intervening
plate between the cardinal and lateral teeth is exceedingly large and very flat.

I dedicate this species to the memory of Rumphius, the author of " D'Amboinsche
Rariteitkamer."

UnIO SAGITTIPORMIS. PI. XXII. Fig. 35.

Testa Isevi, valdi transversa, compressd, ad latere planulatd, valde insequilaterali, postice acute angulaid ;
valvulis subtenuibus ; natibiis parvis, prominuUs, ad apices itndu/atis; epidermide virido-fuscd, radiatd; den-
tibus curdinalibus parvis, compressis, crenulatis; lateralibus prselongis subrectisque; margurila purpurea et
iridescente.

Shell smooth, very wide, compressed, flattened at the side, very inequilateral, acutely angular behind; valves
rather thin; beaks small, slightly prominent, undulated at the tip; epidermis greenish-brown, rayed; cardinal
teeth small, compressed, crenulate; lateral teeth very long and nearly straight; nacre purple and iridescent.

Hab. Oconee river, near Athens, Georgia, Major Le Conte.
My cabinet and cabinet of Major Le Conte.
Diam. .6, Length L2, Breadth 2.7 inches.

Shell smooth, very wide, compressed, flattened at the side, very inequilateral, acutely
angular behind; substance of the shell thin; beaks small, slightly prominent, undulated at
the tip and placed towards the anterior margin; ligament long and thin; epidermis brown-
ish, with numerous broad, dark-green rays, covering the whole disk, with rather distant
lines of growth; posterior slope somewhat compressed, with a single raised line passing
from the beak to the posterior margin; umbonial slope rather acutely angular; cardinal
teeth rather small, compressed, crenulate, double in both valves ; lateral teeth long, nearly
5

34 DESCRIPTION OF NEW

straight, and thickened at the posterior end; anterior cicatrices distinct; posterior cica-
trices conflluent; dorsal cicatrices placed nearly in the centre of the cavity of the beaks;
palleal cicatrix impressed; cavity of the shell very shallow; cavity of the beaks shallow
and rounded ; nacre purple and iridescent.

Remarks. — I have before me two specimens of this species, which belongs to the group
of which the V. jiasalus, Say, may be considered the type. Its form and appearance is
altogether graceful. It perhaps more closely resembles Fisherianiis, (Nobis,) than any
other species, but may be distinguished in being rather less wide, and it differs in having
broader rays. In outline, it resembles U. Barratlianus, (Nobis,) but it is a wider shell,
and not so thick. The two specimens I have are both of a fine purple ; others may differ,
and it may be found white and salmon colour.

Unio Stewardsonii. pi. XXIII. Fig. 36.

Tesln Ixvi, triangulari, compressd, inxquilaterali, postice emarginata,ad basim prselongd, ad latere planu-
laid; valvulis crassis ; natibus prominulis ; epidermide luleo-fusca, radiatd ; dentibtts cardinalibus subcrassis,
crenulatis ; lateralibus brevissimis, crassis, crenulatis rectisque ; margaritd argented et iridescente.

Shell smooth, triangular, compressed, inequilateral, emarginate behind, prolonged at the base and flattened at
the side; valves thick; beaks lather prominent; epidermis yellowish-brown, radiated; cardinal teeth rather thick,
crenulate; lateral teeth very short, thick and straight; nacre silvery white and iridescent.

Hab. Chatanooga river, Tenn., Thomas Stewardson, M. D.
Cabinet of the Academy of Natural Sciences.
Diam. .6, Length 1, Breadth 1.2 inches.

Shell smooth, triangular, compressed, inequilateral, emarginate behind, enlarged and
extended circularly at the base, flattened at the side; substance of the shell thick, thinner
behind; beaks rather prominent; ligament short and rather thin; epidermis yellowish
dull-brown, with numerous capillary rays over most of the disk, and with distant marks
of growth; posterior slope flattened and lighter in colour; umbonial slope obtusely angular;
cardinal teeth rather thick, crenulate, double in both valves; lateral teeth very short, cre-
nulate, thick, nearly straight, and thickened at the posterior end; anterior cicatrices dis-
tinct; posterior cicatrices distinct; dorsal cicatrices placed near to the margin and almost
in connexion with the cardinal tooth; palleal cicatrix impressed; cavity of the shell very
shallow; cavity of the beaks shallow and subangular; nacre silvery white and iridescent.

Remarks. — Among many interesting specimens of some twenty species, brought by
Dr. Stewardson, was a single specimen of this species. It is very closely allied to the
UniofolirtlKs, Hild., and at first I did not hesitate to consider it as a small specimen of
the female of that species, but a very slight examination of the enlargement of that portion
of the shell which indicates the female character, satisfied me that it could not be the
same. In the foUatus the enlargement for the oviducts is always a continuation and
(Milargement of the ridge over the middle of the disk; and immediately before this there
is, in the mature female, a deep indentation. In the Stewardsonii this emarginate part is
replaced by the enlargement, and instead of being indented at the posterior basal margin,

.^^^4.X..^^/^/j:1:^..^ m^^^T

)-lt)

l^•^Jm XatuTf, {^jii.iffan

.^6" /,'/tw SU^yarihonii
37 „ flan If^ttn lis.

10 lu'nti'rumits.

FRESH WATER AND LAND SHELLS. 35

it really is there enlarged. The position, therefore, of the oviducts of the animal, which
I have not seen, must be different. Judging from this single specimen, I should think it
will prove to be a much smaller species than the foliaius of the Ohio.

I name it after Dr. Stewardson, to whose exertions we are indebted for its discovery.

Unio Hanleyianus. pi. XXIII. Fig. 37.

Testd Ixvi, obliqud, tumidd, valde insequilaterali, postice angulata; valvulis percrassis ; natibus grandibus,
tumidis; epidermide bruneo-olivd, striata, eradiatd; dentibus cardbialibus parvis, pyramidalis ; laleralibua
brevis rectisque; margaritd alba et iridescente.

Shell smooth, oblique, swollen, very inequilateral, angular behind; valves very thick; beaks large and
swollen; epidermis brownish-olive, striate, without rays; cardinal teeth small, pyramidal; lateral teeth short and
straight; nacre white and iridescent.

Hab. Coosawattee river, Murray county, Georgia. Dr. Boykin.

My cabinet.
Diam. .8, Length .9, Breadth 1.4 inches.

Shell smooth, oblique, swollen, very inequivalve, angular behind; substance of the shell
very thick, much thinner behind ; beaks large, swollen and placed towards the anterior
margin; ligament short and thin; epidermis brownish-olive, striate, without rays and with
close marks of growth; posterior slope wide and rather depressed ; umbonial slope raised,
very obtu-sely angular; cardinal teeth small, pyramidal, single in the right, and double in
the left valve; lateral teeth short, straight and in a direction much above the cardinal
tooth; anterior cicatrices distinct and deeply impressed; posterior cicatrices distinct;
dorsal cicatrices on the under side of the plate; palleal cicatrix impressed; cavity of the
shell deep and irregularly oval; cavity of the shell shallow and obtusely angular; nacre
white and iridescent.

Remarks. — Three or four specimens are before me, differing very little from each other.
The marks of growth are unusually close together, and are much darker than the inter-
space, which is brownish-olive. It is a pretty little species, and is allied to U. decisus^
(Nobis,) and scalenlus, Raf., and approaches U. pulvinulus, (Nobis.) It differs from the first
in not having the beaks so terminal, and not being so much swollen on the anterior por-
tion of the disk; from the second, in not having the beaks so terminal, in being more
oval and in being without rays. From the last it differs in being less rounded, of a lighter
colour, and having the marks of growth closer.

I dedicate this species to Sylvanus Hanley, Esq., one of the authors of " History of
British Mollusca," &c.

Unio placitus. PI. XXIII. Fig. 38.

Testa Imvi, elHpticd, sicbin/?atd, inisquilaterali, postice subangulatd ; valvulis siibcrassis; natibus subpromi-
nentibus, rntundatis; epidermide castaned, nitidd, obsolete rudiatd; dentibus cardinalibus suhparvis, compre»-
sis, per obliquis, crenulalis; lateralibus sublongis, lamellatis curvisque; margaritd salmonis colore tinctd.

Shell smooth, elliptical, rather inflated, inequilateral, subangular behind; valves a little thick; beaks some-
what prominent, rounded ; epidermis chestnut-coloured, shining, obsoletely rayed ; cardinal tcetli rather small,
compressed, very oblique, crenulate ; lateral teeth rather long, lamellar and curved ; nacre salmon coloured.

36 DESCRIPTION OF NEW

Hab. Alabama, Mr. C. M. Wheatley.
Cabinet of Mr. Wheatley.
Diam. .5, Length .8, Breadth 1.3 inches.

Shell smooth, elliptical, rather inflated, inequilateral, angular behind; substance of the
shell a little thick; beaks somewhat prominent, rounded, ligament short and thin; epider-
mis chestnut-coloured, shining, obsoletely rayed, with rather distant marks of growth;
posterior slope rather depressed; umbonial slope slightly raised and round, cardinal teeth
rather small, compressed, very oblique, crenulate and double in both valves; lateral teeth
rather long, lamellar, curved and separated from the cardinal teeth; anterior cicatrices
distinct; posterior cicatrices confluent; dorsal cicatrices placed on the under side of the
plate; cavity of the shell rather deep and regularly oval; cavity of the beaks small and
subangular; nacre salmon coloured.

Remarks. — This is a small, regular and pretty-looking shell, of which only one specimen
was in Mr. Wheatley's collection. I could not place it in any species known to me. It
may not be a fully grown specimen. It is nearest in outline to U. conslriclus. Con., in
those specimens where the margin is not constricted, which is often the case. It differs
from it in being a thicker shell, more regularly oval, and being fuller on the umbones and
on the umbonial slope. In the rays it also difiers, having fewer, and these being more
distant. It is also rounder on the posterior margin. The nacre of the specimen before
me is of a pale salmon colour, inclining to rose. Other specimens will be likely to vary
in colour.

Unio Troschelianus. pi. XXIII. Fig. 39.

Tenia Ixvi, subobliqnd, convexiuscidd, insequilaterali, postice sitbangtilatd ; valvuHs crassis; nalUms sub-
grandibus : epidermide brimco-oliva, striata, eradiati'i ; dentibus cardihalibus parvis, grunulalis ; lateraUbiis
brei'is, crassis reclisqiie; margaritd alba et iridescentc.

Shell smooth, siiboblique, somewhat convex, inequilateral, subangular behind; valves thick; beaks rather large;
epidermis brownish-olive, striate, without rays; cardinal teeth small, granulate ; lateral teeth short, thick and
straight; nacre white and iridescent.

Hab. Coosawattee river, Murray county, Georgia, Dr. Boykin.
My cabinet.
Diam. .7, Length 1.1, Breadth 1.5 inches.

Shell smooth, rather oblique, somevvhat convex, inequilateral, subangular behind,
rounded before; substance of the shell thick, thinner behind; beaks rather large, sub-
medial; ligament rather short and thin; epidermis brownish-olive, striate, without rays,
and with very close marks of growth; posterior slope somewhat compressed; umbonial
slope rounded; cardinal teeth small, granulate, single in the right and double in the left
valve; lateral teeth short, thick and straight; anterior cicatrices distinct, posterior cica-
trices distinct; dorsal cicatrices placed on the under side of the plate; palleal cicatri.x well
impressed; cavity of the shell rather shallow and rounded; cavity of the beaks very shal-
low and obtusely angular; nacre white and iridescent.

lirmnrks.—Scvora] specimens are before me, neither of which have perfect beaks.

FRESH WATER AND LAND SHELLS. 37

Whether there be undulations at the tips it is impossible to say. In outline, it is some-
what like U. Raveiieliamis, (Nobis,) but it is less oblique and less compressed. It is also
allied to U. nucleopsis. Con., but that is quite round in the outline, while the former is
rather oblique. It is also much more compressed.

I dedicate this species to M. Troschel, who has done much in the anatomy of this family.

Unio Keinerianus. pi. XXIII. Fig. 40.

Test a fiibercidafd, subrolimdatd, subinjla/d, subeqitUaterali; vulvvlis crassis ; not ibus prominent ibus, sub-
medialis; epidermide liiteold, substriatd ; dentibus cardinalibus grandibiis, granulatis crassisque ; lateralibus
brevis, crassis subrectisque ; margaritd albd et iridescente.

Shell tuberculate, subrolund, somewhat inflated, subequilateral ; valves thick, beaks prominent, submedial ;
epidermis yellowish, somewhat striate; cardinal teeth large, granulate and thick; lateral teeth short, thick and
nearly straight; nacre white and iridescent.

Hab. Coosawattee river, Murray county, Georgia, Dr. Boykin.
My cabinet.
Diam. .7, Length 1.1, Breadth 1.3 inches.

Shell sparsely tuberculate, subrotund, somewhat inflated, nearly equilateral, rounded
behind; substance of the shell thick, rather thinner behind; ligament short and rather
thick; epidermis yellowish, somewhat striate near the margin, with very close marks of
growth; posterior slope wide and but slightly raised; umbonial slope rounded; cardinal
teeth large, granulate, thick, double in the left and somewhat trifid in the right valve;
lateral teeth short, thick, nearly straight, far removed from, and in a direction far above
the cardinal tooth, leaving a large plate between the two teeth; anterior cicatrices dis-
tinct; posterior cicatrices distinct; dorsal cicatrices in a row under the cardinal teeth;
palleal cicatrix well impressed; cavity of the shell moderately deep; cavity of the beaks
deep and angular; nacre white and iridescent.

Remarks. — I very much regret that I have not better specimens of this species. The
four before me are all worn in the beaks more or less, and two of them are quite old and
eroded. The two younger ones only have rays. The older of these, here figured, has a
broad, green ray over the middle and anterior portion of the disk, and two small ones on
the posterior slope. On the youngest specimen, about one-fourth grown, there is no
tubercle; on the others they are very few and very small, and placed towards the mar-
gin. These are so small as scarcely to deserve the name. This species belongs to the
group of which JJ. pustiilosus, (Nobis,) may be considered the type. It differs from that
shell in being rounder and having fewer tubercles, in being less angular behind and more
rounded before. It is allied to U. Schoolcraflcnsis, (Nobis,) but that is more quadrate,
having quite a compressed carina, but resembles it in having few tubercles. The two
oldest specimens are slightly impressed before the umbonial slope and are subangular
behind.

I dedicate it to Mr. L. C. Keiner, the author of " Species General ct Icon. Coquil.
Vivantes."

38 DESCRIPTION OF NEW

Unio Ingallsianus. pi. XXIV. Fig. 41.

Testa Isevi, transversa, inflata, cylindraced, postice acuto-angulatd, e natibus postice bilineatis ; valvulis
sublenuibus; natibus subprominentibus ; epidermide tenebroso-olivaced, striata; dentibtts cardinalibus prx-
longis, laminatis el in valvuld dexlrd solum dvpUcibus; lateralibus longis, laminatis, rectis; margaritd
cxruleo-albd et valde iridcscente.

Shell smooth, transverse, inflated, cylindrical, acutely angular behind, with two lines posteriorly from the
beaks ; valves rather thin ; beaks rather prominent ; epidermis dark-olive, striate ; cardinal teeth very long,
lamelliform, straight and in the right valve only double ; lateral teeth long, lamelliform, straight ; nacre bluish-
white and very iridescent.

Hab. Siam, Thomas R. Ingalls, M. D.

My cabinet and cabinet of Dr. Ingalls.
Diam. .7, Length .8, Breadtli 1.9 inches.

Shell smooth, very transverse, inflated, cylindrical, acutely angular behind, obtusely
rounded before, with two minute, slightly elevated lines running from the beaks towards
the posterior margin, on the posterior slope flattened, near the basal margin slightly com-
pressed; substance of the shell rather thin; beaks rather prominent, submedial; ligament
short and rather thick; epidermis dark-olive, dull, striate over the whole disk, without rays;
umbonial slope obtusely angular; cardinal teeth very long, lamelliform, straight, and in
the right valve only, double; lateral teeth long, lamelliform, straight and double in the left
valve; anterior cicatrices confluent; posterior cicatrices confluent; dorsal cicatrices placed
on the plate immediately over the centre of the cavity of the beaks; cavity of the shell
deep and rounded; cavity of the beaks rather shallow and rounded; nacre bluish-white,
pearly and iridescent.

Remarks. — This very interesting shell was sent to me by Dr. Ingalls, of Greenwich, N. Y.
It was the only new one among several he received from Siam. To his kindness for this
and other species, I am indebted, and I dedicate it to him. The form is very unusual, and
assimilates to the U. Cail/audil, Fer., from Egypt. The colour is of the same dull olive.
It may be distinguished in the e.\terior by its being less cylindrical and more angular
behind; and in the interior, by the peculiar form of the cardinal teeth, which are long and
lamelliform and double in the right valve, while in the Caillaudii they are short, erect, and
double in the left valve. The beaks are also much more medial. The nacre is of an
uncommonly fine pearly character, and in this specimen it is delicately striate from the
cavity of the beaks towards the margin. In the description, it may be observed that I
have stated the anterior cicatrices to be confluent, a rather unusual character in the
Uniotics. Of the smaller under cicatrix there is no appearance in this specimen, but it
may be embraced in the large one. There is, however, a very distinct cicatrix above the
large one. It is much to be regretted that the soft parts were not preserved, as the
peculiar cardinal teeth and muscular cicatrices indicate a different disposition of the mus-
cular fibres of the adductor and retractor muscles. The enlargement on the posterior
portion of the disk towards the basal margin, indicates the female character of this
.specimen.

%7::.,.. ^.:/^^^c^2ff^.:st:/hf^j^^

i!J

<

/V". *■««.<•. ir/-*/'".

■tJ I IKii IllllillhuillllS

ita „ inyrJIus

■U iiu.r

II ,. riu/riniis

FRESH WATER AND LAND SHELLS. 39

Unio nigellus. pi. XXIV. Fig. 42.

Testa Isevi, elliplica, anlice compressd, valde insequilalerali, postice ohluso-biangulata ; valvulis tenuibus ;
natibus prominulis; epidermide nitidu, nigra; dentibus cardinalibus parvis,acuminaiis, crenululis; luteralibus
prselongis curvisque; inargarita cseruleo-albd et valde iridescente.

Shell smooth, elliptical, compressed before, very inequilateral, obtusely biangular behind; valves thin; beaks a
little prominent; epidermis shining, black; cardinal teeth small, pointed, crenulale ; lateral teeth long and
curved ; nacre bluish-white and very iridescent.

Hab. Chatahoochee river, near Columbia, Georgia, Dr. Boykin.
My cabinet.
Diam. .5, Length .9, Breadth 1.6 inches.

Shell smooth, elliptical, compressed before, very inequilateral, obtusely biangular behind ;
substance of the shell thin, thicker before; beaks a little prominent and placed near to the
anterior margin; ligament rather long and thin; epidermis shining, black, with distant
marks of growth; posterior slope rather compressed, and with an indented line from the
beaks to the margin; umbonial slope inflated and rounded; cardinal teeth small, pointed,
crenulate ; lateral teeth long, curved and removed from the cardinal teeth ; anterior cica-
trices distinct; posterior cicatrices confluent ; dorsal cicatrices placed above the centre
of the cavity of the beaks; palleal cicatrix impressed; cavity of the shell rather deep;
cavity of the beaks shallow and subangular; nacre white and beautifully iridescent.

Remarks. — A single specimen of this species was received by me some years ago, from
my late friend. Dr. Boykin, to whose kindness I owe many interesting and new species
from the fruitful locality of Columbia. Having never been able to obtain other specimens,
I have delayed until now its description. Older or younger specimens may present dif-
ferent characters. This specimen is in good condition, but the beaks are not perfect, and
in younger and perfect specimens, the epidermis may not be so dark as this. It is allied
to U. occultus, (Nobis,) but is not so compressed nor so high in the carina. The occtiltus
is also much more rayed.

Unio nux. PI. XXIV. Fig. 43.

Testa Ixvi, elliplica, convexd, subinsequilaterali, postice subangulata ; valvulis percrassis ; natibus promi-
nentibus, rotimdatis ; epidermide tencbroso-f used, radiatd; dentibus cardinalibus subgrandibus ; laleralibus
brevis rectisque; margaritd argented et iridescente.

Shell smooth, elliptical, convex, somewhat inequilateral, subangular behind ; valves very thick; beaks prominent,
rounded; epidermis dark-brown, radiated; cardinal teeth rather large; lateral teeth short and straight; nacre very
white and iridescent.

Hab. Alabama river, Mr. Wheatley.

My cabinet and cabinets of Dr. Budd and Mr. C. M. Wheatley, New York.
Diam. .6, Length .8, Breadth, LI inches.

Shell smooth, elliptical, convex, somewhat inequilateral, rounded before, subangular
behind; substance of the shell very thick, much thinner behind; beaks prominent, inflated
towards the umbo; ligament very short and rather thick; epidermis dark-brown, obscurely
radiated, yellow on the posterior slope, with a single curved ray from the beak to the

40 DESCRIPTION OF NEW

margin, marks of growth rather distant and distinct; umbonial slope obtusely angular;
cardinal teeth rather large, double in the right and single in the left valve, crenulate,
pointed; lateral teeth short and straight; anterior cicatrices distinct; posterior cicatrices
distinct ; dorsal cicatrices small and placed on the under side of the plate between the
cardinal and lateral teeth ; cavity of the shell deep and rounded ; cavity of the beaks
rather deep and angular; nacre very white and very iridescent on the posterior portion
of the valve.

Remarks. — There are three specimens before me of this small species. The largest is
scarcely an inch wide, but may not be entirely mature. It looks somewhat like U. decisus,
(Nobis,) but may be distinguished by its colour and by the place and form of the beak.
It is not an oblique species, but in outline more like U. glans, (Nobis.) In the yellow
colour of the posterior slope it resembles U. ehenus, (Nobis,) but it is not so rotund as
that shell, and has the beaks more medial. The posterior portion of the valve is remarka-
bly thin for so thick a species, and the nacre uncommonly pearly and iridescent.

Unio nigrinus. pi. XXIV. Fig. 44.

Testa Isevi, obovatd, sitbinflald, insequilaterali, nigra; valvulis tenuibus; natibus subprominentibus ; den-
tibiis cardinalibus parvis, acuminatis ; lateralibus longis curvisque; margaritd subpurpured et iridescente.

Shell smooth, obovate, somewhat inflated, inequilateral, black ; valves thin ; beaks slightly prominent ; car-
dinal teeth small, pointed ; lateral teeth long and curved ; nacre somewhat purple and iridescent.

Hab. West Florida, Major Le Conte.
Cabinet of Major Le Conte.
Diam. .7, Length LI, Breadth L9 inches.

Shell smooth, reversely ovate, somewhat inflated, inequilateral, rounded before and
behind, black; substance of the shell thin; beaks slightly prominent and approaching the
anterior margin; ligament short and very thin; epidermis smooth, somewhat shining,
black, with very indistinct rays and approximate lines of growth ; cardinal teeth small,
double in both valves, pointed and more acuminate on the anterior division; lateral teeth
long, thin and curved ; anterior cicatrices distinct; posterior cicatrices confluent; dorsal
cicatrices placed in the centre of the cavity of the beaks; cavity of the shell rather deep
and rounded; cavity of the beaks shallow and slightly angular; nacre somewhat purple
and very iridescent posteriorly.

Remarks. — A single specimen of this species, not very perfect, and eroded at the
beaks, was among the West Florida shells from Major Le Conte. In outline, it ap-
proaches U. ajnygdaliim, (Nobis,) but differs in being a larger shell, thinner, black on the
outside and purple within. It is not so purple as the U. ciiprinus, (Nobis,) nor is it so
light in the epidermis. It is also nearly allied to U. occultus, (Nobis,) but is not so wide
a species and is rounder on the umbonial slope.

FRESH WATER AND LAND SHELLS. 41

Anodonta denigrata. pi. XXV. Fig. 45.

Testa Isevi, dliptica, convexiusculd, inxquilaterali, antice rolundata; valvulis tenuibus; nalibus prominu-
/Is, ad apices undulalis ; epidermide politci, bruneo-nigricente, obsolete radiatu ; margaritd caeruled alba et
iridescente.

Shell smooth, elliptical, somewhat inflated, inequilateral, rounded before; valves thin, beaks slightly prominent,
undulated at the lip; epidermis polished, blackish-brown, obscurely rayed; nacre bluish- while and iridescent.

Hab. Campbell county, East Tennessee, President Estabrook.
My cabinet and cabinet of President Estabrook.
Diam. .8, Length 1.2, Breadth 2.2 inches.

Shell smooth, elliptical, somewhat inflated, inequilateral, rounded before and very
shghtly flattened on the anterior part, with a slightly curved dorsal line a little irregular
near the point of the beak; substance of the shell thin, very slightly thicker and whiter
before; beaks very small and very slightly prominent, rather concentrically undulate at
the tip; ligament thin and rather long; epidermis polished, blackish-brown, sometimes
dark-grecnish-brown, and obtusely rayed, with distant marks of growth. Posterior slope
rather wide, and not much compressed; with three rather obscure dark-green rays, from
the beak to the posterior margin; umbonial slope rounded and but slightly raised; anterior
cicatrices confluent; posterior cicatrices confluent; dorsal cicatrices immediately above
the centre of the cavity of the beaks; cavity of the shell not very deep, oval; cavity of
the beaks very shallow and rounded; nacre bluish-white and iridescent.

Remarks. — This is rather a small species, of which President Estabrook sent me some
dozen specimens. It is a distinct species, and more nearly alhcd to An. Ferussaciana,
(Nobis,) than to any other species. It differs in being a smaller species, in being more
compressed, and in having a much less callus on the dorsal margin. Indeed, in some of
the specimens no callus can be perceived. The undulations of the beaks are simple and
nearly concentric, like the Ferussaciana, but they are smaller. In all the specimens but a
half-grown one, there is a rough, opake, white, carious mark of disease about the anterior
cicatrix and the cavity of the beaks. The younger one is without this mark of disease.
This specimen is greenish, and has the lines of growth very distinctly marked.

Anodonta opaca. PI. XXV. Fig. 46.

Testa Isevi, ellipticd, subinflatd, inxquilaterali, posiice angulatd ; valvulis tenuibus ; natibus subpromi-
nentibus, ad apices undulatis ; epidermide opaca, nigricente, obsolete radiata ; margaritd albd et iridescente.

Shi;ll smooth, elliptical, rather inflated, inequilateral, angular behind; valves thin, beaks rather prominent,
undulate at the tip ; epidermis dark, almost black, obscurely rayed ; nacre white and iridescent.

Hab. Near New Orleans, Mons. Janin. Little Rock, Arkansas, Prof Powell.
My cabinet and cabinets of Prof. Powell and Dr. Hale.
Diam. 1.5, Length 2.1, Breadth 3.4 inches.

Shell smooth, elliptical, rather inflated, inequilateral, angular behind, slightly curved on
the dorsal line; substance of the shell thin; beaks rather prominent and undulated at the
tip; ligament rather short and somewhat thick; epidermis dark, almost black, coarsely
6

42 DESCRIPTION OF NEW

Striate, obscurely rayed, witli distant lines of growth; posterior slope wide, very dark,
and with obscure rays; umbonial slope very obscurely angular; anterior cicatrices con-
fluent; posterior cicatrices confluent; dorsal cicatrices placed anterior to the cavity of the
beaks; palleal cicatrix scarcely perceptible; cavity of the shell rather deep and oval;
cavity of the beaks rather shallow and rounded; nacre white and iridescent.

Remarks. — I have had several specimens of this species many years, and have had great
difficulty where to place it. It is nearest allied to An.Jluvialilis, — a species which has a
most remarkably extended geographical range; but it seems to me to differ too much to
retain it in that species. It diff'ers in being less transverse, in the beaks being more medial,
and in the epidermis being darker. It is also a little more enlarged on the umbonial
slope. Being always very desirous to keep the number of our species as limited as pos-
sible, I very often defer for years describing specimens as new, which I cannot place
satisfactorily with those already characterized. More recently, I have received from
Prof. Powell several specimens of the same characteristics, from Little Rock, and I think it
will be found by the naturalists of Louisiana and Arkansas, whence it comes, that the cha-
racters will be found constantly to diflfer enough to distinguish it from fuviat'dis, which
flourishes more than any other Anodonta in the middle states.

Anodonta Californiensis. pi. XXV. Fig. 47.

Test a stibalaiu, Issvi, clliptica, sitbinflatii, postice rolundata; valvuUs temdbus ; natibits mlnittis, ml apices
vndulalis; epidermide virido-olivacea, nitidii ; margarila albc'i et iridesccnle.

SluU subalale, smooth, ellipiical, somewhat inflated, rounded behind; valves thin, beaks very small and
undulated at the tips; epidermis olive-coloured, shining; nacre white and iridescent.

Hab. Rio Colorado, California, J. L. Le Conte, M. D.
My cabinet and cabinet of Major Le Conte.
Diam. .8, Length 1.3, Breadth 2.2 inches.

Shell subalate, smooth, elliptical, somewhat inflated, rounded behind, slightly compressed
towards the anterior basal margin; substance of the shell thin and fragile, beaks very
small, scarcely rising above the dorsal line, finely undulate at the tip; ligament rather
short and thin; epidermis virido-olivacea, shining, with rather distant marks of growth;
posterior slope rather broad, compressed and raised nearly into a wing, with three dis-
tinct green rays from the beak to the margin; umbonial slope inflated and rounded;
anterior cicatrices distinct; posterior cicatrices confluent; dorsal cicatrices nearly in the
centre of the beaks; palleal cicatrix scarcely visible; cavity of the shell rather deep;
cavity of the beaks exceedingly shallow; nacre white.

Remarks. — Dr. Le Conte procured but two or three specimens of this, which was the
only species of the family Naiades he saw in California. This marks a very singular dif-
ference in the existence of these forms of animal life, from those in the waters of the more
eastern states, where they exist in such profusion, and in such a great number of various
forms and habits. This species is more nearly allied, indeed it is closely allied to An. Nitt-
lal/ianct, which I described many years since, and which was brought by Mr. Nuttall from

■J^^r^..^.^.,^^5^..?'^6^:eJ, "p^^/^^.

^rY\

IramiWttOrt hrHtb-'t

■t5 jlnodonlu dt'/iiifrii/<i

'Id „ opaca .

41 „ Ca/tf^irrni'itsts .

FRESH WATER AND LAND SHELLS. 43

Wahlamat river, in Oregon. It differs in being a smaller species, in being more inflated,
and particularly so in the superior part. In this shell the umbonial slope is smaller from
the beaks to the posterior dorsal margin. In the NultaUiana the upper portion of the
umbonial slope is flattened, but it enlarges towards the posterior basal margin, and there
makes the greater diameter. In the Califonncnsis the greatest diameter is about the
middle of the disk, and there is a marked difference in the wing, which is by no means so
much elevated.

Anodonta Trautwiniana. pi. XXVI. Fig. 48.

Testa Isevi, oblongd, subinjlatd, imeqinlateruli, e natibus linealis ; valvuJis crassis; nalibus prominuUa, ad
apices minute undulatd: epidermide virido-olivaced, rugoso-striutd ; margaritd argented et iridescente.

Shell smooth, oblong, somewhat inflated, inequilateral, with a line from the beaks; valves thick; beaks some-
what prominent, at the tips minutely undulated; epidermis greenish-olive and roughly striate; nacre silvery and
iridescent.

Hab. Carthagena, South America, John C. Trautwine, Esq.

My cabinet and cabinet of the Academy of Natural Science.
Diam. .9, Length 1.5, Breadth 2..5 inches.

Shell smooth, oblong, somewhat inflated, inequilateral, obtusely rounded before, subalate
behind, with a line from the beaks to the posterior margin; substance of the shell thick;
beaks somewhat prominent, submedial, at the beaks very minutely undulated; ligament
very long and thin, not protruding above the dorsal line of the valves; epidermis greenish-
olive, and roughly striate, quite imbricate behind, without rays; umbonial slope elevated
into a carina; anterior cicatrices distinct; posterior cicatrices confluent; dorsal cicatrices
none; palleal cicatrix slightly impressed; cavity of the shell rather deep and rounded;
cavity of the beak very shallow and subangular; nacre silvery white, with minute striae
from the beaks towards the margin; iridescent.

Remarks. — The friends of Mr. Trautwine owe to him the possession of this interesting
species, of which he brought many specimens, and liberally distributed them. It differs
from any South American species which has come under my notice. It is a much
smaller species than An. trapczialis, Lam., rougher in the epidermis and more oblong.
Some of the specimens are somewhat greenish, others yellowish-olive. The triangular
fosset at the end of the ligament, so usual in the South American Naiades, is very per-
ceptible in this species.

In outline, it is allied to tetragona, (Nobis.)

Anodonta Wheatleyi. PI. XXVI. Fig. 49.

Testa Isevi, transversa, subinjlatd, gibbosd, valde insequilaterali, poslice angulafd, anlice irregularite.r
rotundatd; valviilis crasals ; nulibiis lianidis, pannn ehvalis, fere terrninalibus ; epidermide cinnamomea,
eradiatd ; margaritd salmonis colore lincta et valde iridescente.

Shell smooth, transverse, rather inflated, gibbous, very inequilateral, angular behind, irregularly rounded
before; valves thick ; beaks swollen, a little elevated and almost terminal; epidermis cinnamon-red and rayless;
nacre salmon-coloured and very iridescent.

44 DESCRIPTION OF NEW

Hab. Para, South America, Mr. C. M. Wheatley.
My cabinet and cabinet of Mr. Wheatley.
Diam. .8, Length 1.1, Breadth 2.2 inches.

Shell smooth, transverse, rather inflated, gibbous, very inequilateral, angular behind,
irregularly rounded before, slightly compressed near to the anterior margin and straight
on the dorsal line; substance of the shell thick; beaks swollen, a little elevated and placed
near to the anterior margin ; ligament very long and very thin, scarcely protruding above
the dorsal line; epidermis cinnamon-red, reddish-brown along the margin, totally without
rays, the lines of growth approximate; posterior slope very long, rather wide, somewhat
compressed, with a thin, coloured, elevated hair-like line passing from the beaks to the
posterior margin; uinbonial slope elevated and rounded; anterior cicatrices distinct, the
smaller one very minute; posterior cicatrices confluent; no visible dorsal cicatrices; pal-
leal cicatrices slightly impressed; cavity of shell rather shallow; cavity of the beaks rather
shallow and subangular; nacre with minute striae from the beaks towards the margin,
of a beautiful light salmon colour, and magnificently iridescent.

Remarks. — Of this beautiful South American Anodonla, I have but a single specimen
before me. It differs from any of the species described by Spix or D'Orbigny, and is
altogether a very remarkable species. It is a stout shell, with a nacre which is softer,
richer and more satin-like than in any I have ever seen. The nacre is a light salmon
colour, with a tint of purple, which gives the most surprising softness and brilliancy to it.
The margin is dark, but the nacre immediately in contact with it gives a line of fine blue
and green. The triangular fosset at the end of the ligament, common to the South
American species, is very marked in this.

I owe this and many other fine sheHs of this family to my friend Mr. Wheatley, and I
dedicate this beautiful one to him.

Anodonta Shaefferiana. pi. XXVI. Fig. 50.

Testa Isevi, oblonga, injlata, insequilaferali, postice angulata; valvulis subcrassis; nalibus prominentibun,
ad apices unchihili.s- ; ephlermide castaneii, nitida, obsolete radiatii; margaritd salmonis colore tinctti.

Shell smooth, oblong, inflated, inequilateral, angular behind; valves rather thick; beaks somewhat prominent,
undulated at the beaks; epidermis shining, chestnut-coloured and obsoletely rayed; nacre salmon coloured.

Hab. Horn Lake Creek, Tenn,, Mr. Shaeffer.

My cabinet and cabinet of Mr. Shaeffer.
Diam. 1.2, Length 1.7, Breadth 2.8 inches.

Shell smooth, oblong, inflated, inequilateral, angular behind, rounded before; dorsal
line under the beak, interrupted by a double, tuberculous callus; substance of the shell
thick; beaks someAvhat prominent, submcdial, coarsely undulated at the tip; ligament
rather short and thick; epidermis shining, chestnut coloured, obsoletely rayed, with dis-
tinct distant marks of growth; posterior slope broad and somewhat flattened; umbonial
slope angular from beak to margin; anterior cicatrices confluent; posterior cicatrices con-
fluent; dorsal cicatrices placed above the cavity of the beaks and partly on the tuberculate
swellings; palleal cicatrix slightly impressed; cavity of the shell deep and broad; cavity
of the beaks deep and subangular; nacre salmon-coloured and brilliant.

A...>. d,M/, ^^<^. ' ^2/^/7)^ M

/'.un.VjtO/T' by tbbtftSOT.

18 Jrui(Jun/(i Trou/winitiiiii .
f,9 „ Wlmilhyi.

50 ., Shiie/fi'rinntt. .

/

FRESH WATER AND LAND SHELLS. 45

Remm-ks. — This species is nearly allied to A. tctragona, (Nobis,) but seems to me too
distinct to be considered the same. The outline is much the same, but the tuberculous
swellings under the beak are more enlarged than in that species. The umbonial angle is
also more sharp. There are two specimens before me, both of which have beautiful sal-
mon-coloured nacre. A third specimen, also from Mr. Shaefler, marked " Missouri," is
somewhat like the others, but approaches more to some of the varieties of areolalus, Swain.*

I owe this and several other fine shells to Mr. Shaeffer, an ardent collector of Cincinnati,
and I name this one after him.

Anodonta Linn^na. pi. XXVII. Fig. 51.

Tesld l:em, rolundata, valde injlalu, siibxquilatcrali, post ice obtuse angulalu; valvidls suhtemiibus ;
natibiis prominent ibus, ad apices riigoso-iindulalis ; epidermide luleo-viridi, niiidd, striata, obsolete radiuta;
margaritd salmonis colore tinctd ct iridescente.

Shell smooth, rotund, very much inflated, nearly equilateral, obtusely angular behind; valves rather thin;
beaks prominent and rugosely undulate at the tip; epidermis yellowish-green, shining, striate, obscurely rayed;
nacre salmon-coloured and iridescent.

Hab. Lake Concordia, Louisiana, Mr. C. M. Wheatley.
My cabinet and cabinet of Mr. Wheatley.
Diam. L9, Length 2.8, Breadth 4.1 inches.

Shell smooth, rotund, much inflated, nearly equilateral, obtusely angular behind ; very
much inflated and rounded at the umbones, curved on the dorsal line; substance of the
shell rather thin; beaks prominent, inflated, and rugosely wrinkled at the tip; ligament
rather short and somewhat thick; epidermis yellowish-green, shining, rather roughly
striate, obscurely rayed and very dark on the posterior slope; posterior slope broad,
short, rather flattened, and very rugose; umbonial slope angular; anterior cicatrices con-
fluent; posterior cicatrices confluent; dorsal cicatrices placed near to the edge, some dis-
tance anterior to the point of the beaks; palleal cicatrix scarcely visible; cavity of the
shell very deep and rounded; cavity of the beaks deep and rounded; nacre beautifully
salmon-coloured, rich, and iridescent, leaving a very broad border round the margin.

Remarks. — This is the finest species of Aiiodonta I have seen from our country. It
is most beautifully coloured in the nacre, which is exceedingly brilliant. A single speci-
men only is before me, and this is' somewhat fractured. The margin is very uncom-
monly broad, without any pearly nacre, and Avhite. The epidermis is rough with stria?,
and yet it looks rich and pleasing. The green rays are broad and iridescent. This
species is allied to An. glohosa, (Nobis,) from Mexico; but it differs much in the smooth-
ness and polish which the latter shell has. The beaks are more medial and the margin

* When in Cincinnati, neaily two years since, Mr. J. Clarke gave me a suite of a species o( .Inodonia which
he considers to be the true edcntida of Mr. Say, described in "The Disseminator." 'I'hcy were taken from the
river Ohio, near that city, and are not found in Mill Creek, near by, where the areolatiis abounds. He says
that they difl'er in the beaks, and in the outline they appear to me to difier very much,— the Ohio shell being
very wide and oblong, while the Mill (^reek shell is oval, and usually larger. The latter is also more rayed.

46 DESCRIPTION OF NEW

much broader. In colour they are entirely different. One is white, the other salmon-
coloured. The fosset at the end of the ligament is remarkably large and curved.

This beautiful species I dedicate to the memory of the great master in natural science,
Linnceiis.

Anodonta oblita. pi. XXVIII. Fig. 52.

Tesid Isevl, ell'ipticd, compressd, inmquUutcraU, postice subbians^idatd ; vatvulis pertenuibus ; nalibitx
prominiilis, ad apices tmdidatis ; epidermide nitidu, bruneo-viridi, obsolete radiutd; margarild cxnded alba
et iridescente.

Shell smooth, elliptical, compressed, inequilateral, subbiangular behind; valves very thin; beaks slightly
prominent, undulated at the tip ; epidermis shining, brownish-green, obscurely radiated ; nacre bluish-while and
iridescent.

Hab. Campbell county, East Tennessee, President Estabrook.
My cabinet and cabinet of President Estabrook.
Diam. .7, Length 1.2, Breadth 2 inches.

Shell smooth, elliptical, compressed, inequilateral, subbiangular behind, rounded before
and slightly flattened on the anterior portion of the disk, with a simple curved dorsal line;
substance of the shell very thin; beaks very small, slightly prominent and undulate at the
tip; ligament rather thin and not very long; epidermis shining, brownish-green, obscurely
rayed, with rather distant marks of growth ; posterior slope rather narrow and some-
what compressed, with three distinct and somewhat distant green rays from the beaks to
the posterior margin; umbonial slope rounded and considerably raised; anterior cicatrices
confluent; posterior cicatrices confluent; dorsal cicatrices on the inside of the dorsal line;
cavity of the shell very shallow; cavity of the beaks very shallow; nacre bluish-white
and iridescent.

Remarks. — I received but three specimens from President Estabrook of this species.
The largest, although small, seems to be adult. The green colour of the posterior por-
tion of the valve is dark and fine. There are here three rather broad and unusually dis-
tinct rays, the inferior one being the largest, and well over the umbonial slope. The
anterior portion of the disk is darker and brownish. This species is perhaps the nearest
allied to An. denigrala, herein described. It may be distinguished by its being more
compressed, greener and smaller.

Anodonta virens. PI. XXVIII. Fig. 53.

Testa Isevi, ellipticd, ventricossissirnd, insequilaterali, postice subangulatd; valvulis tenuibus; natibus
proniinentibiis, valde liimidis, ad apices riigoso-undulatis; epidermide viridi, politd, obsolete radiald ; mar-
garild albd et iridescente.

Shell smooth, elliptical, very much inflated, inequilateral, subangular behind ; valves thin ; beaks prominent,
very much swollen and rugosely undulate at the tip ; epidermis green, polished, obscurely radiated; nacre white
and iridescent.

Hab. Red river, at Alexandria, Louisiana, J. Hale, M. D.
My cabinet and cabinet of Dr. Hale.
Diam. 1.9, Length 2.3, Breadth 3.5 inches.

%,u.>. ^,. 4J.'yrr. ?'^,%,r.>. ' /r/ /rK // S7.

JIT ;r,i

'vY„

V

V

X

— ..-^yf-

^

ytoin M,Uun: In /l-bolAin

,'il . httu/i/iiiti Liiiiiri'ttiuf .

FRESH WATER A^D LAND SHELLS. 47

Shell smooth, elhptical, very much inflated, inequilateral, subangular behind, angular at
the anterior dorsal margin, very much inflated and somewhat gibbous on the umbones,
nearly straight on the dorsal line; substance of the shell thin; beaks prominent, very much
swollen and rugosely wrinkled at the tip; ligament rather short and somewhat thick;
epidermis green, polished, slightly striate, obscurely rayed, with three rather obscure rays
on the posterior slope, and with distant marks of growth; posterior slope very wide,
rather short, and rather depressed; umbonial slope rounded, with an irregular, slightly
raised line from the beaks to the posterior margin; anterior cicatrices confluent; posterior
cicatrices confluent; dorsal cicatrices invisible; palleal cicatrix not observable; cavity of
the shell very deep and rounded; cavity of the beaks deep and rounded; nacre white and
iridescent.

Remarks. — Several specimens are before me, of different ages. It is perhaps most
nearly allied to An. Slcwartiana, (Nobis,) but is more rotund, more inflated and smoother
on the epidermis. In some of its characteristics, it approaches the An. Lhimmna, (Nobis,)
described in this paper. It differs from that in being less rotund, in having a smoother
and more polished epidermis, and it diff"ers entirely in the nacre, which is not salmon-
coloured, nor so thick or brilliant.

Anodonta tortilis. pi. XXVIII. Fig. 54.

Testa plicatd, obovatd, stibcompressd, inasguilalerali, e natibus minute lineatis; valuulis subtenuibus ;
natibus prominulis ; epidermide olivaced, minute tortile; margaritd cxruleo-albd et iridescente.

Shell plicate, obovate, somewhat compressed, inequilateral, minutely lined from the beaks ; beaks a little
prominent; valves rather thin ; epidermis olive, minutely wreathed; nacre bluish-white and iridescent.

Hab. Carthagena, South America, J. C. Trautwine, Esq.
My cabinet.
Diam. .5, Length .9, Breadth 1.4 inches.

Shell plicate, obovate, somewhat compressed, inequilateral, rather obtusely rounded
before and subalate behind, with a minute line from the beaks to the posterior margin;
substance of the shell rather thin; beaks a little prominent, submedial; ligament rather
long and thin; epidermis olive, minutely wreathed nearly over the whole disk, without
rays; umbonial slope compressed and elevated into a carina; anterior cicatrices confluent;
posterior cicatrices confluent; dorsal cicatrices none; cavity of the shell rather shallow;
cavity of the beaks very shallow and subangular; nacre bluish-white, iridescent, with
minute strire from the beaks to the margin.

Remarks. — It is to be regretted that only a single specimen of this shell should have
been found by Mr. Trautwine, to whose kindness I owe the possession of it. It is
remarkable for the minute wreaths of the epidermis, which are distributed in festoons
over most of the disk. In these wreaths it resembles the An. crispata. Lam., which is the
only species of the family I have seen with this singular character. The specimen before
me has the beaks beautifully tinged with a greenish hue, being epidermal matter deposited
between the layers of nacreous matter. In the cavity of the beaks this shows quite con-
spicuously, and is stronger in two divergent lines. Under the lens, in this specimen, a

48 DESCRIPTION OF NEW

number of minute impressions may be observed in both valves, posterior to the anterior
cicatrix. Whether these are muscular attachments or not I am not certain ; older and
thicker specimens would enable one to judge. It has the triangular fosset common to
the South American species. The margin is broad for the size of the shell, and the
granules of it are very perceptible with a microscope of good power.

This species comes so near in its characters to the An. crispata, my specimen of which
came from Cayenne, that it is with some hesitation that I have separated it. The tortitis
has the festooned crimples much finer, and they do not extend over the whole disk,
as in the crispata, nor are they by any means so much impressed, but change into striae
on the posterior slope and on the anterior portion of the disk. The loriilis is also rather
longer and more compressed towards the beaks. On the crispata the festooned crimples
are much coarser, and the marks of growth are difibrent. Dr. Gould, in the Proceedings
of the Boston Society of Natural History, November, 1850, described an Anodo7ita, under
the name of glauca, brought by the Exploring Expedition, which I believed at the time to
be the crispata, Lam. The specimen seemed to me to be of the same species with that
which I procured from Ferussac, in Paris, under the name of crispata. The name of
glaitca also is preoccupied by Valencienes, for Q.x\o\he,r Anodonta from South America. It
is with some hesitation I place this in the division of "plicate" species, as it almost
requires a lens to see the folds, but it cannot be called a " smooth " shell.

«

Anodonta Schroteriana. pi. XXIX. Fig. 55.

Testa Imvi, transversa, subcompressa, valde inxquilaterati, postice obtuso-biangulari ; valvulis subcrassis;
naitbus prominentibxs, acittis; epidermide riigosd, crebrissime striata, tenebroso-olivd, obsolete radiatd;
margaritd albd et iridescente.

Sliell smooth, transverse, rather compressed, very inequilateral, obtusely angular behind ; valves rather thick;
beaks prominent and pointed; epidermis rough, thickly striated, dark-olive, indistinctly radiated ; nacre while
and iridescent.

Hab. Rio Negro, Brazil, Mr. C. M. Wheatley.

My cabinet and cabinet of Mr. Wheatley.
Diam. .9, Length L5, Breadth, 3.1 inches.

Shell smooth, transverse, rather compressed, very inequilateral, obtusely biangular
behind, slightly compressed on the sides near the middle of the dorsal line, with a slight
callus under the beaks; substance of the shell rather thick ; beaks prominent, pointed and
placed towards the anterior margin; ligament long and rather thin; epidermis very rough,
covered with very close crimpled strife, dark-olive, with a few indistinct rays over the
posterior slope, and with rather distant lines of growth; posterior slope long, compressed
into a carina; umbonial slope slightly raised and rounded; anterior cicatrices distinct, the
smaller one very minute; posterior cicatrices confluent; no visible dorsal cicatrices; pal-
leal cicatrices slightly impressed ; cavity of the shell rather shallow and wide ; cavity of
the beaks shallow and angular; nacre with minute strice from the beaks towards the mar-
jjin, white and iridescent.

Remarks. — A single specimen, or rather the two valves of different individuals, was
kindly given to me by Mr. Wheatley. It does not seem to have been noticed by Spix or

%^m^d^M//^.^^&uM7h>^'^^

.;.?

S

^

,'>2 Aiiinliiutti vblilii .
M ■ ■ yiri'ris .

54 .. lorlilis.

Ftaai n.uiirr hf Jhbolron

! .

FRESH WATER AND LAND SHELLS. 49

by D'Orbigny. It is very peculiar in the texture of the epidermis, which is crimpled up
into irregular, somewhat parallel, very close, rugose lines, which cover the whole surface
of the disk. In both of these valves there is a distinct muscular impression above the
great anterior cicatrix, which I have not observed before in any of the Anodonlse. The
absence of a dorsal cicatrix is also unusual; but in this it resembles some of the other
South American species, viz.: Anodonta enslforrnis, Spix, solemformis, D'Orb, &c. In
outline it is nearly allied to An. exilis, (Nobis,) but it has not the straight dorsal line,
is a thicker shell, and has a very different epidermis. The triangular fossct at the end
of the ligament is rather large and well marked. The riglit valve has a few black pen-
cilled marks in the nacre, such as are sometimes seen in the South American Anodontse.
These are remarkable as being nearly parallel, and in a direction pointing to the beaks.
They look as if made by a pen, with black ink.

I name this fine species in honour of the memory of Schrostcr, author of Flusconchlien,
&c.

Anodonta Arkansensis. PL XXIX. Fig. 56.

Testa laev'i, eUiplica, compressd, valde inasquilalemli, postici subhinnguhifd ; vahttlis crassis; nalibus
subprominentibus, ad apices undulatis ; epidermide sitbviridi, radiald, striata; margaritd cceruleo-ulbd.

Shell smooth, elliptical, compressed, very inequilateral, subbiangular behind; valves thick; beaks rather
prominent and undulated at the lip ; epidermis greenish, rayed ; nacre bluish-white.

Hab. Little Arkansas, J. L. Le Conte, M. D.
Cabinet of Major Le Conte.
Diam. ,9, Length L7, Breadth 3 inches.

Shell smooth, elliptical, compressed, subbiangular behind and rounded before, sub-
angular on the posterior slope; substance of the shell thick; beaks rather prominent,
pointed, with three or four large undulations at the tip; ligament long and rather thin;
epidermis greenish, striate, with unequal transverse marks of growth, dark on the pos-
terior slope, with indistinct, broad greenish rays over the disk; posterior slope with two
lines from the beak to the posterior margin; dorsal margin slightly curved, and having a
callus immediately under the beak almost amounting to a tooth; anterior cicatrices dis-
tinct; posterior cicatrices confluent; dorsal cicatrices placed on the lower part of the
callus; cavity of the shell rather shallow; cavity of the beaks shallow and angular; nacre
bluish-white, leaving a broad dark margin.

Remarks. — A single specimen of this interesting species has been submitted to me by
Dr. J. L. Le Conte, who obtained it on a late scientific excursion to the Rocky Moun-
tains, from the Little Arkansas, where the road to Santa Fe crosses it. This species is
not likely to be confounded with any other known to me, and belongs to that group which
has an irregular thickening or callus under the beak on the dorsal margin, which, while
it does not amount to a tooth, makes a very distinct natural group. This callus is not
so large and marked as to be confounded with D'Orbigny's genus Mnnocondylxa ; but it
may be compared witli that o( Alasmodonta edenlula, Say, which is a true Anodonta. Tiio
form of this species is more lenticular than in any other of the genus I know; and look-
7

50 DESCRIPTION OP NEW FRESH WATER AND LAND SHELLS.

ing on the exterior reminds us of Symphyiwta compressa, (Nobis,) changed to U. pressus,
(Nobis.) The undulations of the beaks are large, and the epidermis of them being thin,
gives the tip a whitish appearance.

-r^

y^,, l.../l/(r^C^''^>^'^^r/k/y'/f>

55

56

\

/

/

.'i.'i Jiunliiiiht Si-hnil.Tuuiit
.'it') .. Arkiiiisi'iisi.f .

l\(»n oithirf llV Ihlwtfl'll

DESCRIPTION OF A NEW GENUS (BASISTOMA,) OF THE FAMILY MELANIANA,

TOGETHER WITH

SOME NEW SPECIES OF AMERICAN MELANI^E.

FAMILY MELANIANA.

GENUS BASISTOMA.*

Testa conica. ^ertura ovata, basi abscissa. Labrum acutum. Columella Issvi. Operculum .

The particular shell for which I propose this genus was given to me by Amory
Edwards, Esq., late the Consul of the United States at Rio, who brought it from four
hundred miles up the river Tocatinus, five hundred miles distant from the ocean, at the
mouth of the Amazon. It differs from any of the family of Melaniana in the cut at the
base, and it has none at the superior part of the aperture. It comes near to Pirena, but
wants the superior cut, and it differs from Melanopsis in its general form as well as in
having no callus on the columella. The Melaniana being so enormously developed, and
having but few genera, I think it advisable to constitute new ones, whenever a group can
be well characterized, which is the case with this form. I think that Melania transversa,
(Nobis,) from Guiana, and M. Braziliensis, (Nobis,) would properly come under this
division, and very likely other characteristic species will be found in that portion of South
America whence these three come. The genus Melaioma, Swainson, is a well charac-
terized group in some respects near to this. While it is emarginate at base, it has an
emargination also towards the upper portion of the outer lip, and the group, as far as I
know it, has a general and well characterized outline, being somewhat mitraform. I
think that my M. microstoma, tornatella and rudis all belong to a group which would con-
stitute a new genus, unless it could be put into one of Mr. Svvainson's genera, all the
types of which I have not seen.

* /3a(rt{, base, and •t't/tnj, to cut.

When I proposed the name of Schizostomu for a genus of Melaniana with a cut at the superior portion of
the aperture, I was not aware that M. Bronn liad already used that name for a fossil genus. I now propose to
substitute Schizochilus, from nxti^a, to nit, and ;{">■''«> Hp-

52 DESCRIPTION OP NEW

I very much regret that the operculum did not accompany this specimen, suspecting,
as I do, that it will be found to differ from the genus Mclania, and be somewhat like
M. transversa, which I propose above to bring into this group. The operculum of this lat-
ter species was described by me as having the polar point near the centre, and having
five revolutions.*

Basistoma Edwardsii. PL XXX. Fig. 1.

Testa striata, tttrrili'i, sxibcrassa, geniculatd, tenebroso-corned; spird valde atlenuatd; suttiris valde im-
pressis; anfractibiis phnmlutis; siiperne impressis, Uneis crebrissimis instructis ; aperturd sitbgrandi,
ellipticd, intus albidd, ad basim valde abscissa; columella Ixvi torlaque.

Shell striate, turreted, rather thick, geniculate, dark horn-colour; spire very much drawn out; sutures very
much impressed ; whorls flattened, impressed above, thickly covered with revolving lines; aperture rather large,
elliptical, white within, at the base abruptly cut off; columella smooth and twisted.

Hab. River Tocatinus, South America, Amory Edwards, Esq.
My cabinet.
Diam. .50, Length 1.92, of an inch.

Remarks. — This very beautiful and interesting shell is remarkable for the new form it
presents in the aperture. It is thickly striate all over the whorls, and looks like a suc-
cession of coils of rope piled on each other. The two lower whorls are impressed above
the middle, which gives it a geniculate character immediately below the suture. Between
the strise there are very minute sculptured points. The apex being eroded, the number
of whorls are not ascertainable, but they are probably about ten. The outer lip is very
sharply edged, and the central portion very much extended on a curve. The aperture is
about one-fourth the length of the shell.

The form of this species reminds one of Achaiina columna {Lymnea coliimnaris,
Lamarck,) which is however, a land shell. It is drawn out like it and has flattened
sides, with a cut at the base of nearly the same form. In other characters they are not
at all alike, the columna being sinistral, covered with granules, much larger and belong-
ing to a diflferent genus altogether.

I dedicate this fine species to my friend Mr. Edwards, to whom I am indebted for it
and many other interesting shells from the waters and banks of the Amazon.

Melania perstriata. pi. XXX. Fig. 2.

Testd striatd, aciiloconoided, aiibtenui, cinnamomeo-bnined ; spird elevatd, suhattenuatd, ad apice carinutd
el granulatd; suturis impressis; anfraclibus seplenis, convexis; aperturd parva, ellipticd, ad basim angulata,
intus rufd; columella Ixvi.

Shell striate, acutely conical, rather thin, cinnamon-brown; spire elevated, somewhat attenuate, at the apex
carinate and granulate; sutures impressed, whorls seven, convex ; aperture small, elliptical, angular at the base,
reddish within; columella smooth.

* Proceedings Zoological Soc, London, 1851, p. 187.

FRESH WATER AND LAND SHELLS. O^i

Hab. Coosa river, Alabama, Prof. Brumby. Huntsville, Tenn., Mr. J. Clark. Tennessee,
Prof. Troost.

My cabinet and cabinets of Prof. Brumby and Mr. Clarke,
Diam. .28, Length .83, of an inch.

Remarks. — Among the numerous Melanix sent to me long since by my late friend Prof.
Troost, were several specimens of the young of this species. I could n ot satisfactorily
place them in any known species, and I put them temporarily with siriatula, (Nobis,)
which is strongly allied to the species which I have described above. Recently, I have
received from Prof. Brumby and from Mr. J. Clark several adult specimens, which leave the
younger in my possession no longer in doubt,^-they were recognised at once to belong to
those more recently received. All the specimens — some dozen — before me are reddish;
the striatula is horn-coloured, with a white aperture. The latter is also flatter in the
whorls, and not so carinate above, nor are the sutures so deeply impressed. Some of the
specimens are quite smooth on the body whorl. Aperture about one-third the length of
the shell.

Melania sculptilss. pi. XXX. Fig. 3.

Testa perstriatd, conoided, sublemn, corned; spird acuminata, ad apicem carinatd et granulatd ; sutiiria
irreguhtriler impressis ; anfraclibus dechn, subplunulalis ; striis crebris et inter sculpturald ; aperturd parvd,
ellipticd, ad basim angulatd, intus albidd ; columelld inciirvd tortdque.

Shell thickly striate, conical, rather thin, horn colour; spire pointed, towards the apex carinate and granulate;
sutures irregularly impressed; whorls ten, rather flattened; striae close, and between them sculptured; aperture
small, elliptical, angular at base, white within; columella incurved and twisted.

Hab. Tennessee, Mr. J. Clark.

My cabinet and cabinet of Mr. Clark.
Diam. .24, Length .55, of an inch.

Remarks. — Two specimens are before me, which are precisely alike. It is a very
remarkable species, having regular and close strite over the whole of the lower whorls,
between which strise there is a double row of minute indented marks, very close to each
other, and only visible with a lens. I have seen no such marks on any other species.
In outline it is closely allied to striatula, (Nobis,) but it is a smaller species, and has not
the cancellation of that species. The aperture is rather more than one-third the length
of the shell. The outer lip is broken.

' Melanl\ Clarkh. pi. XXX. Fig. 4.

Testa plicald, claviforrnis, sicbtenui, tenebroso-fuscd ; spird elevald, attemtatd; suturis subimpressis ;
anfraclibus planulatis ; aperturd parvd, subeUipticd, ad basim angulatd, intus tenebrosd ; columelld tortd.

Shell folded, club-shaped, rather thin, dark-brown; spire elevated, drawn out; sutures somewhat impressed;
whorls flattened; aperture small, rather elliptical, at the base angular, within dark; columella twisted.

Hab. Duck Creek, Tenn., Mr. Joseph Clark.

My cabinet and cabinet of Mr. Clark.
Diam. .23, Length .73, of an inch.

54 DESCRIPTION OF NEW

Remarks. — Tlie form of this species is more attenuate than usual with the clavate forms.
It has about ten whorls; those above the body whorl being disposed to be both plicate
and striate. Towards the apex they are all thickly striate. On all the specimens before
me, on the lower whorls, there are irregular oblique striae, somewhat similar to those on
the M. Ocoeiinsis, (Nobis,) which give them a malleate character. On the upper margin
of the whorls, along the sutures, there is usually an indistinct light line. The outer lip is
broken.

Melania Brumbyi. Pi. XXX. Fig. 5.

T^esta striata, pyramidati'i, snbcrassa, ritfo-hrunea ; spird valde elevald, ad apice carinatd : suturis vix
impressis ; anfractibits plannlalis ; aperturd subgrandi, rhomboided, inlns ncbiginosd ; cohimelld torld.

Shell striate, pyramidal, rather thick, reddish-brown ; spire very much elevated, carinate at the apex ; sutures
but slightly impressed ; whorls flattened; aperture rather large, rhomboidal, within rubiginose; columella twisted.

^ -Hab. Coosa river, Alabama, Prof. Brumby. Huntsville, Alabama, Mr. J. Clark.

My cabinet and cabinets of Prof. Brumby and Mr. Clark.
Diam. .53, Length 1.72, of an inch.

Reinarks. — This is a very remarkable species, and among the largest of our Melanise.
In form and size it is allied to annuUfera,, Con., but may easily be distinguished by its more
numerous strise, its reddish colour, and the form of its aperture, which is more open. In
the Brumbyi there is an angle in the middle of the whorl, which gives the aperture a
rhomboidal form. The columella is rufous and the channel whitish. The apex of each
of them being broken, the number of whorls cannot be correctly ascertained. I should
suppose there were at least ten. Some of the specimens here are beautifully granulate
between the stria;. The aperture is not quite one-fourth the length of the shell. Along
the suture, on the upper part of the whorl, there is a line of a lighter colour than the
other part.

I dedicate this species to Prof. R. T. Brumby, who has done so much in bringing to
light the interesting shells of Alabama.

■fc>

Melania oblita. PI. XXX. Fig. G.

Testa valde carinald, turritd, cochlexformis, subtenui, corned; spird attenuatd; suturis linearibus; an/rac-
tibus duodecim, anile carinatd; aperturd parvd, eUiplicd, intus albidd ; columella alba torldque.

Shell very much carinated, turreted, screw-shaped, rather thin, horn-coloured; spire drawn out; sutures
linear ; whorls twelve, acutely carinate ; aperture small, elliplical, witliin whitish ; columella white and twisted.

Hab. Tennessee?

My cabinet.
Diam. .30, Length .96, of an inch.

Remarks. — I have about a dozen of this species, which is very distinct from any
with which I am acquainted. The locality I am uncertain about, the label being by
some accident lost. I believe it comes from Tennessee, but am not certain. Its very
marked character of a screw, or rather the end of a gimlet, strikes one at once. In
most species there is a thread-like line above the carina and several below. The carina

FRESH WATER AND LAND SHELLS. OO

is not usually persistent on the body whorl. It is nearest in form and size to M. j^ercarinata,
Con., but may be easily distinguished by the absence of granules between the carinse,
the length of the spire, having three or four more whorls, and in being less shining. The
aperture is not quite one-third the length of the shell.

Melania fubva. pi. XXX. Fig. 7.

Testci lasvi, conoided, svbcrassd fitrvd; spird subelevaid ; sutitris excavatis ; anfractibns phnnilatis : apcr-
turd parvd, subrhomhoided, ad basim angulatd, inlus purpurea ; columeUd purpurea tortaque.

Shell sraoolli, conical, rather thick, dusky ; spire rather elevated ; sutures furrowed ; whorls flattened ; aper-
ture small, subrhoraboidal, at the base angular, within purplish ; columella purple and twisted.

Hab. Branch of Coosa River, Alabama, Prof. Brumby.
My cabinet and cabinet of Prof. Brumby.
Diam. .30, Length .84, of an inch.

Remarks. — A single specimen of this species was received from Prof. Brumby. It has
the apex so much eroded as to present only a little more than three whorls, which are,
however, perfect, and enable me to distinguish it from its allied species, the nearest of
which is M. arata, (Nobis.) The sutures have the same furrowed line, and the sides of
the whorl are alike flattened. The aperture, however, differs in form and colour. In the
arata the columella is straight down to the channel at the base; in the furva, it is curved
to the right and the channel is less marked. The length of the aperture, in perfect speci-
mens, must be about one-third the length of the shell.

The Alexandrensis, (Nobis,) from Louisiana, is very closely allied to this species, and
when perfect specimens of both shall be obtained, they may possibly be found to be the
same.

Melania Sellersiana. PI. XXX. Fig. 8.

Tesid plicatd, parvd, conoided, subcrassd, bruneo-nigricente ; spird subbrevi; suturis linearibus; anfrac-
tibus subconvexis ; aperturd magna, elliplica, ad basim rotundatd, inlus purpured ; coluineUd valde incurvatd.

Shell folded, small, conical, rather thick, very dark-brown ; spire rather short ; sutures linear ; whorls slightly
convex ; aperture large, elliptical, rounded at the base, within purple ; columella very much incurved.

Hab. Cany Fork, Tennessee, Mr. Coleman Sellers.

My cabinet and cabinets of Mr. Sellers and Mr. Anthony.
Diam. .16, Length .38, of an inch.

Remarks. — This is an interesting little species, somewhat like M. NicHhu'ana, (Nobis,)
in its general appearance and size, but is less inflated, and of a darker colour. It might
be supposed that its being a plicate shell would at once distinguish it; but the Sellersiana
seems to be very variable in the character of its folds, some of the specimens really
having none remaining. These may have had folds near the apex, which is now eroded.
Some of those before me are beautifully folded down to the last half of the body whorl,
the folds being rather large and straight. The surface varies very much; some of the
specimens being beautifully mallcate, while on others no such marks can be observed.
The outer lip is broken.

56 DESCRIPTION OF NEW

The apex being eroded in all the specimens, I am not sure of the number of the whorls;
there may be about six. The aperture is about one-half the length of the shell.
I dedicate this species to Mr. Coleman Sellers, of Cincinnati.

Melania oppugnata. pi. XXX. Fig. 9.

Testa Isvi, truncatd, cylindraced, percrassd, luteo-corned ; spira truncatd; szituris magnis el valde irregu-
lariler impressis; anfractibus valde compressis, superne geniculatis; aperlurd prselongd, valde constricld,
siiperne callosd, intits albd ; cohimelld torld, superne valde incrassatd.

Shell smooth, truncate, cylindrical, very thick, yellowish horn-colour; spire cut off; sutures large anil very
irregularly impressed; whorls very much compressed, geniculate above; aperture very long, very much nar-
rowed, above callous, within white; columella twisted, and very much thickened above.

Hab. Alabama river, Mr. C. M. Wheatley.

My cabinet and cabinet of Mr. Wheatley.
Diam. .41, ' Length ?

Remarks. — This is a very remarkable species. The two specimens before me are both
cut off, leaving little more than the body whorl. When taken they were evidently living
and healthy specimens, but the eroded and fractured spires give them the appearance of
old and diseased shells, which is by no means the case. The upper part of the whorl,
along the suture, is irregularly fractured round the whole circle. This arises from the
fact that the animal having filled up the channel with calcareous deposit, suddenly re-
commences at a new line of growth, some distance below, leaving open and bare of epi-
dermal matter this upper portion of the channel, which consequently having a sharp edge,
becomes more or less fractured. The whorls are so much flattened that the two sides are
nearly parallel. One of the specimens has a small spot of brown in the aperture above
and below — the other has none. This species is allied to auriculafomis, (Nobis,) on one
side, and olivula, Con., on the other, but it may be easily distinguished from both of them.
The former is a smaller shell and more fusiform; the latter is more conical, less thickened
on the columella, and not irregularly fractured in the suture. The number of whorls or
proportional size of the aperture cannot be ascertained on the specimens before me.
They have the appearance of having been very much exposed to an attacking enemy,
hence the name.

Melania Saffordii. PL XXX. Fig. 10.

Testa Ixvi, obtuso-conoided, crussd, subfusiformis, lenebroso-viridl; spird sitbbrevi; suturis linearibvs;
anfractibus convexiusculus, tdtimo magno; aperturd subgrandi, ovato-productd, inttis purpured; cohtmelld
purpitred tortdque.

Shell smooth, obtusely conical, thick, subfusiform, dark-green ; spire rather short; sutures linear; whorls a
little convex, the last large; aperture rather large, ovately elongated, within purple; columella purple and
twisted.

Hab. Lebanon, Wilson county, Tennessee, Mr. James M. Safibrd.
My cabinet and cabinet of Mr. SafTbrd.
Diam. ..37 Length .85, of an inch.

FRESH WATER AND LAND SHELLS. -i I

Remarks. — This is a very distinct species, with a not uncommon form. The green
colour is unusual. On the upper part of the whorl, and on the line of the suture there is a
light or brownish band. The body whorl is rather suddenly enlarged in the middle, which
gives it a slight gibbous appearance, and it is irregularly transversely striate. The apex
of each of the three specimens under my examination being eroded, the number of whorls
cannot be exactly ascertained, but I think there must be about six. The aperture is quite
one-half the length of the shell. It is allied to M. sordida, (Nobis,) in outline, but may
easily be distinguished in colour and the gibbous swelling on the whorls. I name this
after Mr. Safibrd, to whose kindness I owe this and some other fine specimens from
Tennessee.

Melania pinguis. pi. XXX. Fig. 11.

Testa Ixvi, inflata, subrotundd, percrassd, tenebroso-fuscd ; spird obtuso-conoided ; siilnris impressis ;
anfractibus convexiuscidus ; aj)crturd ntagnd, rolmidald,intiis vel alba vcl purpurea ; columella incurvd,
incrassatd.

Shell smooth, inflated, almost round, very thick, dark-brown; spire very obtusely conical; sutures impressed;
whorls a little convex; aperture very large and rounded^ within either white or purple; columella incurved and
thickened.

Hab. Lebanon, Wilson county, Tenn., Mr. J. M. Safford.
My cabinet and cabinet of Mr. Safford.
Diam. .34, Length .53 of an inch.

Remarks. — I have three specimens before me from Mr. Safford; two of them are pur-
ple within and one white. None of them are perfect on the apex, but I presume that the
number of whorls must be five. One of the specimens has four. In outline it is very
much like M. injlala, (Nobis,) but it differs totally in the form of the columella. In that
species the columella is twisted backwards, and makes an angular oblique channel — in
the phi guis it is regularly curved, with scarcely a perceptible indentation in the place of
a channel. The aperture is fully one-half the length of the shell.

Melania gibbosa. PI. XXX. Fig. 12.

Testa Ixvi, parvd, obtuso-conoided, gibbosa, sub/usiformi, subtenui, virido-corned ; spird obtusd; suturin
irregulariter impressis; anfractibus quinque, subconvexd ; aperturd magnd, cUiptird, intus bivitlata; coluinelld
rubiginosd, incrassatd, planulatd, impressd et valdi curvatd.

Shell smooth, small, obtusely conical, gibbous, subfusiform, rather tliin, grccnisli horn-colour; spire obtuse,
sutures irregularly impressed ; whorls five, somewhat convex; aperture large, ellijiticai, within double banded;
columella rubiginose, thickened, flattened, impressed and much curved.

Hab. Scioto river, Ohio, Mr. C. M. VVheatley.

My cabinet and cabinet of Mr. Wheatley.
Diam. .25, Length .43, of an inch.

Remarks. — This is a small, ver;^ remarkable species. There is a slight depression
above the middle of the whorl, which gives it a somewhat gibbous form. The most un-
usual character pertaining to this species is, however, the very flat and impressed columella,
8

.)8 DESCRIPTION OF NEW FRESH WATER AND LAND SHELLS.

more impressed at the point of the umbilical region. The columella on the upper part of
these two specimens is not thickened, but it is of a dark-brown colour, and being also
dark below, the colour extends to the outer side of the whorl, and there makes two rather
indistinct bands. In outline it is allied to M.fusiformis, (Nobis,) but they differ entirely
in the columella and in the length of the aperture. The aperture is rather more than
one-half the length of the shell.

I have had some doubts of the Scioto being the real habitat of this shell; but Mr.
VVhcatlcy says it was sent from thence to liini. It seems to have a more southern aspect.

DESCRIPTION OF A NEW SPECIES OF HELIX,

TROM CALIFORNIA,

AND A NEW CHARACTERISTIC FORM OF CERTAIN AMERICAN COLIMACEiE.

Helix Lecontii. PI. XXX. Fig. 13

D'

Testa plano-convexd, in/erne convexd, papillosd, bruneo-corned, late umbilicatu, tridentatd, intus columnd
accessione instrucid; anfractibus senis; aperturd subrotundatu, constrictd; labro hipatico, reflexo, bidentato ;
colutnelld uno-dentatd.

Shell plano-convex, convex below, papillose, brownish horn-colour, widely umbilicated, Ihree toothed, furnished
with an ac<;essory column within; whorls six; aperture rounded, constricted; outer lip diill-brown, redexed, luo-
toothed ; columella one-toothed.

Hab. St. Francisco, J. L. Le Conte, M. D.

My cabinet and cabinet of Dr. Le Conte.
Diam. .27, Length .15, of an inch.

Remarks. — This is a very beautiful little species, which is allied in some of its charac-
ters to hirsuta. Say, iiijlecta. Say, and Lcai, Ward. It is about the size, outline and
colour of the last, and the umbilicus is of the same size. It differs, however, in the teeth,
the Leai having none on the outer lip; and in the papillce, which are smaller, rounder and
closer in the Leai. The tooth on the columella is alike in both, being long, white, and
incurved. Like the inflecta, it has two teeth on the outer lip, but these are much larger
and whiter in the itifleda, which differs also in having the umbilicus closed, and in the
papillae being less distinct. In colour it is like a brown hirsuta, but it differs in being
smaller, in being umbilicate, and in having two teeth on the outer lip, instead of a sinus,
as in hirsuta, which has a much larger tooth on the columella, and a much more con-
stricted aperture.

Fig. 13, b represents the papillae enlarged.

Neither of the few specimens brought by Dr. Le Conte has the animal alive, which, of
course, will remain yet to be described. The papillae cover the whole surface. On the
upper portion of the whorls they are close and elongate, passing into the form of striae.
On the lower portion they are more rounded and beautifully displayed. It is very proba-
ble that in some very perfect specimens, they may be found to have a hirsute character.

I dedicate this species to Dr. Le Conte, whose enterprising researches in Califortiia
have brought to our knowledge many new forms in other branches of natural history.

60 DESCRIPTION OF NEW

Accessory Column in the Family Colimacea.

Wlicn recently cxntniniiig very closely the structure of some of our Ildiccs, I observed
what had before escaped my attention, a pillar or an additional colunui, placed like a
fulcrum (buttress) in the interior, against the wall of the ordinary column, at the distance
of a fifth to a third of a revolution of the whorl from the aperture. I first observed it on
the Carocolla sphiosa, (Nobis,) and followed up this discovery until I detected it in a num-
ber of species and three different genera, admitting Carocol/a, of Lamarck, and Polygyra,
of Say, to be distinct genera, which I think it better at present to recognise.

This fulcrum, as I propose to call it, in distinction from the central column, varies
in form, in size and in place in different species; and at a future period I may give a more
exact account and a fuller description than I am enabled at present to take the time to do.
It is generally visible from the exterior by the naked eye, when the specimen is thin and
in a perfect state. With the assistance of a lens it may be easily seen, though not per-
fectly examined and defined. For this purpose it is necessary to fracture the portion of
the shell in the vicinity of the fnkrum. It will be found in some species to be a simple
round column soldered to the paries of the main column; in others, a compressed or flat-
tened column, extending into the cavity of the whorl.

The purpose of this fulcrum or buttress is very evidently instituted for the greater
strength of the ultimate whorl, which being very much enlarged, seems, in some of these
more delicate species to require additional support.

I have detected the fulcrum in the following species, and as several of the species of
Dr. Binney and Dr. Gould are unknown to me, I think it likely to be found in some of
tlicm.

Carocolla spinosa. Lea. Helix Icporina, Gould.

" Edgariana, Lea. " Lecontii, Lea.

Helix hirsuta. Say. Polygyra Troostiana, Lea.

" monodon. Racket. " Dorfuilliana, Lea.

" Leai, Ward.

It is due to my friend Dr. Leidy to say, that, when I informed him, some months since,
of my having observed this fulcrum in many of the Helices, that he at once informed
ine that while engaged on the anatomical portion of Dr. Binney's work, which he accom-
plished for that zoologist, he had observed in the Helix hirsuta this character of the shell,
and advised Dr. Binney of it at the time. But it seems that he did not take advantage
of Dr. Lcidy's information, or he may not have himself detected, on examination, this
important additional character to these species.

While I have the Polygyra Troostiana and P. Dorfeuilliana before me, I will take the
opportunity to express my dissent to these species being placed by Dr. Binney and Dr.
(iou'd, as synonymous with Helix faligia(a,Siiy. They are not only entirely distinct
from fatigioti, but are distinct in themselves, and I am sure that zoologists who may

'W'.^K-A'

Wv

4

4

%

HuxLslfmui

hilwurihit

:« Mefnitm

Kniinhvt

in

Mrlanui

r SulUmli

Mffttnifi

st'tilphhs

(i ''

ithbtu

f'nrra

>i

n„rl.i,

..

Sellrrxmiin

It

llrh,

l.ni'iilii

FRESH WATER AND LAND SHELLS. 61

procure good specimens of both, will, on a critical examination, declare them to be differ-
ent from each other and distinct from fall g into .

In the very learned and elaborate work of" the late Dr. Binney, " Terrestrial Air-Breath-
ing Mollusks of the United States," he takes occasion to state his strong disapprobation
of the use of personal names for species in natural history, and at the same time points
out a case where he considered it had been carried, to an abuse by a naturalist of this
city. I wish simply, in answer, to give an opinion on the subject, first premising, that
Dr. Binney had himself, in at least two instances, applied personal names to his own
species, few of which he made, committing a graver error than those who do not disap-
prove of the use of personal names.

There are several reasons, in my opinion, why they may be used:

1st. Most of the great naturalists, for nearly one hundred years, have used them with-
out hesitation; and the most distinguished of modern writers have sanctioned the example
by following it; as Lamarck, in Hc/ix Bonp/andii, &ic.; Ferussac, in Helix Richardii, die,
as well also other eminent writers in various branches of natural history.

2d. It is a good substitute, where a well recognised descriptive name cannot be applied,
which is often the case.

3d. It is an honourable acknowledgment of services performed by co-labourers in the
field of science, and it is a gratification due to ardent collectors, who labour for the man
of science at a distance, and often in parts of the world subject to disease and other
dantjers.

Some very distinguished naturalists have gone much beyond the simple use of proper
names for species, for they have applied them even to genera. For instance, Lesueur's
genus Dlachiria; Tremenville's genus Rissoa ; D'Orbigny's genus Acostsea, &:c. &c.

In botany, personal names thus applied to genera have been most extensively used.
In zoology I do not consider this necessary or desirable, but I do think there is not only
a convenience in using such names for species, but sometimes almost an imperative
necessity for it. In very extensive genera, where many hundred species abound, as in
the genera Unio, Melania, Comis, &c., &c., it would be impossible to obtain descriptive
names for all.

SYSTEMATIC INDEX.

Unio affinus, .
Barrattii,
buxeus, .
Clarki.inus,
concavus,
Cuvierianus,
decoralus,
Floridensis,
Forbesianus,
fraternus,
Gibbesianus,
hebes, .
Hanleyianus,
ineptiis, .
Ingallsianus,
Keinerianus,
Kleinianus,
Lamarckianus,
Lazarus,
luridus,
merus, .
Moussonianus,
nigellus,
nigerrimus,
nigrinus,
nux,

Oregonensis,
perslriatus,
placitus,
Powellii,
Prevoslianiis,
proximus,
pygmsEHS,
Reeveianus,
rufusculus,

Pajre

27

U

nio Rumphianus, .

12

" sagittiformis, .

17

" satiir,

29

' sordidus,

16

' Slewardsonii, .

19

' succissus,

13

' Troschelianus,

30

" Tuomeyi,

20

' Whiteianus, .

19

Anodoiita Arkansensis, .

10

' Californiensis,

23

' denigtata,

35

" Linnaeana,

17

' oblila,

38

' opaca,

37

' Schroteriana,

21

' Schafferiana,

22

' torlilis,

15

' Trautwiniana,

29

" virens,

16

' Wheatleyi,

24

Basis

toma Edwardsii, .

39

Melania Brumbyi,

24

' Clarkii, .

40

" furva,

39

' gibbosa, .

31

' oblita, .

11

' oppugnata,

35

' perstriata,

20

' pinguis, .

25

' Saffordii,

27

' sculptilis,

18

" Sellersiana, .

28

Heli>

c Le Conlii,

14

Page

32
33
21
10
34
31
36
12
14
49
42
41
45
46
41
48
44
47
43
46
43
52
54
53
55
57
54
56
52
57
56
53
55
59

I-

.4