7 
genus Hemisolasma , having shell ovate , (ms 
submedialy lamellar teeth subequal. 
118 Sp. Uniofulgens , [ Lampsitis fulgens .] 
Shell thick, elliptical, swelled, attenuated 
behind, outside nearly smooth, laminated, 
ferruginous brown; inside of a beautiful me- 
tallic incarnate and iridescent. Length 1-2, 
diameter 1-3, axis 1-5 of the breadth. 
From the river Ganges, two or three 
inches, beautiful shell, a true Lampsilis , with 
a long flexuose lamellar tooth subcrenulate; 
cardinal tooth compressed crenulate. Ante- 
rior fossule, very conspicuous below the an- 
terior impression. 
119 Sp. Unio argyratus , [Lampsilis argy- 
ratus .] 
Shell thin, elliptical, swelled, attenuated 
behind, outside laminated greenish, decorica- 
ted and silvery at the summit, inside bluish 
iridescent. Length 1-2, diameter 1-3, axis 
1-1 6 of the breadth 
Also from the river Ganges. Size one and 
a-kalf inch. Very near to the S. G. Lepto- 
dea , but teeth as in the last, cardinal small 
crenulate, lamellar less flexuose, not crenu- 
late. In both the teeth are wide apart as in 
all the Lampsilis. 
120 Sp. Unio corrugata, of the authors 
from the river Baramputra, it is an Obliqua- 
ria , very near to my U. Venus and U. Ellip- 
tica, S. G. Jlximedia. In Mr. Poulson’s Ca- 
binet, 1 have not yet been able to determine 
precisely whether it is well named, and not 
having the specimen before me, I cannot de- 
scribe it. 
10 N. G. LONCOSILLA. 
Shell transversal, unequilateral, some- 
what gaping, only one muscular impression 
anteriorly. No teeth as in Jlnodonta , but a 
hinge with a marginal nerve, or fold anteri- 
orly; distinct from the margin, and a little 
obliqual behind. Ligament small at the very 
summit. — Animal unknown. 
A distinct genus of the tribe dnodonta, 
which had been mistaken for a fluviatile So- 
len by Dr. Burroughs the discoverer of it; but 
all the Solens are marine shells. The name 
means little knife: it is different from all my 
S. G. of Anodonta. 
121 Sp. Loncosilla solenoides f or Jlnodonta 
solenoides. Shell elliptic, somewhat swelled, 
both ends rounded and a little gaping, back 
horizontal, outside and inside smooth and 
whitish. Length 1-3, diameter 2-7, axis 
3-7 of the breadth. 
From the river Jellinghy in Bengal. 
Small, seldom one inch long. Posterior 
nerve of the hinge short. 
Addition.— 11th N. G. DIANISOT3S. 
The examination of these Asiatic shells, 
enables me to affirm decidedly that the Sym- 
phonota bialata of Lea is also a peculiar ge- 
nus, very different from our Metaptera } near- 
er to Hiria and Diplasma. I have seen it 
in Mr. Poulson’s cabinet, and ascertained 
that it has, like Lasmonos , a lamellar tooth 
on each side, forming a curve as in Diplas- 
ma, but these teeth appear simple, not fork- 
ed, ahd the two unequal ears , [whence my 
name] or wings distinguish it as Metaptem 
from Unio , and Pecten from Ostrea. 
I propose to call it Dianisotis chinensis , as 
bialata is not a specific but generic charac- 
ter. I could see no cardinal tooth. 
SUPPLEMENT 
On the Fossil Bivalve Shells of the 
Western Region. 
Almost all the fossil bivalves of the 
western states from Ohio to Alabama, belong 
to the great order of Terebratulites or rather 
Brachiopites, whose animals of G. Brachiopus 
were very different from those of the living 
bivalve shells, having ciliate limbs. My mono- 
graph of 1821 contained 23 genera, all new 
except five [and about 80 species] and five 
others had already been published in 1819 
by me in my account of 70 N. G. of 
animals, Journal de Physique. 
1 propose to give an epitome of this mono- 
graph which 1 have not yet seen in print. 
1 possess nearly all the shells. They are 
found in the secondary strata of limestone, 
slate and sandstone which extend from Lake 
Erie to the Gulf of Mexico, in horizontal 
strata, the limestone being the lowest, and 
the sandstone the highest, forming|in many 
parts hills and ridges from 100 to 500 feet 
high. They are very rare in the slate. 
Order BRACHIOPIA. 
Animal brachiopus when living, brachiopites 
when fossil. Shell bivalve, animal within 
having a bilobed mantle, and two thick 
ciliate arms or limbs. 
I. Family, LINGULARIA. Shell equi- 
valve, longitudinal, inequilateral, valves en- 
tire, not perforated, 1, G. Lingula of 
Brugiere. 
II. Family TEREBRARIA. Shell ine- 
quivalve, one valve perforated or emargina- 
ted. 
1st Section, Macrilia. Shell longitudinal. 
2 G. Diclisma, Raf. Equilateral, the 
two valves split at the summit. 
3 G. Apleurotis Raf. 1819. Inequila 
teral, the great valve perforate, and with a 
lateral wing. 
4 G. Trigorima, Raf. Equilateral, 
smaller valve perforate, four cavities at the 
base separated by three septa. 
5 G. Obovites, Raf. Equilateral, the 
great valve perforate. 
6 G. Magas (Sowerby) equilateral, great 
valve with an angular opening. 
2d Section, Isilia. Shell equilateral, 
nearly equital or hardly transversal. 
7 G. Terebratula (Brugiere) great valve 
perforate. 
8 G. Spinifer [Sowerby] subequital, 
great valve with an angular opening, hinge 
with two spiral appendages. 
9 G. Gonotrema, Raf. Shell subtrans- 
versal, small valve with an angular opening, 
and interval cavity, hinge short, straight 
or curved. 
3d Section, Platilia. Shell equilateral, 
transversal or very broad. 
