366 Description of some New Shells. 
Art. XI.—Description of some new Shells, belonging to the coast of 
} New England; by Jos. G. Torren. 
Solemya borealis. Se Ahh A frost rh 
See the plate, Fig. 1. h. 7. 
Shell thin and fragile, oblong : hinge edentulous, placed near the 
anterior end, with a slightly prominent cartilage, and an interior ele- 
vated callus, which is hollowed and forked beneath, the lower portion 
being directed towards the anterior-basal margin: valves distinctly 
wrinkled concentrically along the anterior-dorsal margin, elsewhere 
radiated with from fifteen to twenty sets of lines, which consist of 
two lines, and are distinct on the anterior and posterior portions, and 
of more numerous and rather indistinct lines on the middle of the 
valve : epidermis dark brown, lighter between the sets of lines, very 
glossy, extending much beyond the basal and lateral edges of the 
valves, and, at the hinge-margin connecting them together nearly the 
whole length of the shell: within grayish blue: wmbo destitute of 
the slightest elevation: anterior and posterzor margins rounded : 
superior and inferior margins nearly parallel, the former rectilinear 
except at the ligament where it is slightly emarginate, the latter a lit- 
tle arcuated. . 
Length, 2-65 inches. 
Breadth, 0-85 of an inch. 
Diameter, 0°55 of an inch. 
Tnhabits the coast of Rhode Island. 
I have found this shell only in the vicinity of Newport, where it 
is very rare—and I do not know that it has been found elsewhere. 
On comparing the above with Say’s description of S. velum 
(Journal of the Academy of Natural Sciences of Philadephia—vol. 
2. p. 317) it will be perceived that there is a close accordance 
—his language, wherever it would apply, having been purposely 
adopted: still there is thought to be a specific difference, because, 
Ist. as to size.—A great many shells answering his description 
have been found near the locality of the above shell, but none of 
greater length than one inch. 
2d. as to color.—There are now before me specimens of the 
present shell from the length given above down tothe length of one inch, ; 
and the color is, alike im all, dark brown without, and grayish blue with- 
in, and— 
