CONCHOLOGICAL WRITINGS. 85 
121 Sp. Loncosilla solenoides, or Anodonta 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 2-7 of the breadth. 
From the river Jellinghy in Bengal. Small, seldom one inch long. 
Posterior nerve of the hinge short. 
Addition.—11th N. G@. DIANISOTIS. 
The examination of these Asiatic shells, enables me’to affirm 
decidedly that the Symphonota bialata of Lea is also a peculiar 
genus, very different from our Metaptera, nearer to Hiria and 
Diplasma. J haveseen it in Mr. Poulson’s cabinet, and ascertained 
that it has, like Zasmonos, a lamellar tooth on each side, forming a 
curve as in Diplasma, but these teeth appear simple, not forked, and 
the two unequal ears, [whence my name] or wings distinguish it as 
Metaptera from Unio, and Pecten from Ostrea. 
I propose to call it Dianisotis chinensis, as bialatais not a speci- 
fic but generic character. 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 
monograph 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. 
I propose to give an epitome of this monograph which I have not 
yet seen in print. I 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, form- 
ing 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 haying a bilobed mantle, and two thick ciliate 
arms or limbs. 
