22 / 
the three holes in the lower valve as sufficient to demand for them a 
distinct genus. Bruguiere has made out four species, three of which 
are fossil. Being unacquainted with these fossils, I have, for their 
illustration, copied the representation of the lower valve of C.personata, 
Lam. Anomia craniolaris, Linn. Plate XVI. Fig. 3, from Plate vn. ot 
Hist. Nat. ties Coquilles, par Bose. 
CLII. Terebratala. A regular shell, fixed by a cartilage or short 
tube, and composed of two unequal valves, the largest of which has 
its beak produced and pierced with a hole, through which the cartilage 
passes. The hinge with two teeth. 
After having abstracted from the Linnsean genus Anomia , the shells 
forming the genera Anomia , Crania , Calceola, and Hyalesa, it was 
intended, by Lamarck, to place under the present genus Terebratula, 
the remainder of those shells which had been hitherto considered as 
Anomise. But considerable difficulty will be still found to exist, as to 
the classification of these shells. Mr. Martin, whose accuracy and judg- 
ment, displayed in the division of the shells of this genus, might alone 
suffice to render his work highly valuable, and to make every lover of 
science regret his loss, has shown that, among these shells, there exist 
much greater differences than Lamarck is apprized of. He iound it 
necessary, on this account, to arrange them in the four following 
families : — 1. Imperforated, with one valve flat, and with a straight, 
extended, and narrow hinge. 2. Perforated, both valves convex ; the 
hinge straight and patulous, with a large trigonal foramen between the 
beaks : these are subdivided into those with a long or a short hinge. 
3. Perforated, both valves convex ; the beak of the larger valve incum- 
bent, with a very small trigonal or oblong foramen : the hinge close 
and curved. 4. Perforated, both valves convex, the beak of the larger 
valve pierced by a tubular opening ; the hinge close and curved. 
It is evident, that, of these four families, the shells of the two last 
only can be placed, in strictness, under this genus — the imperforated, 
and those with a large trigonal foramen between the beaks, cannot be 
