4*76 K. J. BvsJi, — Molhtsca of Cape Hatteras. 



Venericardia obliqua, sp. nov. 



Shell small, moderately thick, compressed, somewhat triangular, 

 very oblique, much produced anteriorly. Beaks small, acute, curved 

 inward and very much forward. Surface crossed by from twelve to 

 fourteen principal radiating ribs and two or three smaller ones on 

 either side. The ribs are broad, flat, roughened by the lines of 

 growth and separated by narrow, rather deep, unequal grooves. In- 

 terior smooth, very lustrous, semi-transparent, the external ribs show- 

 ing distinctly through, and at their termination, forming broad crenu- 

 lations in the margin. Hinge plate very broad, with a single prom- 

 inent, slightly oblique, wedge shaped, bilobed tooth directly under 

 the beak, in the right valve, with a deep triangular cavity on either 

 side ; and in the left valve two stout, divergent, wedged shape 

 teeth, with a deep, triangular cavity betw^een. Color dirty white 

 with a broad, median, concentric band of yellow-brown. 



Length of a medium sized specimen, 6""" ; height, 6*5 ; thickness, 



omm 



One living specimen and a few single valves, in 7 to 10 fathoms. 

 Chama congregata Conrad. 



Fossils Tertiary Form. U. S., p. 32, pi. 17, fig. 2, 1838. 

 Separate valves occurred in 1 to 27 fathoms and living specimens, 

 in 16 fathoms. 



Liicina filosa stimp. 



Gould, Invert. Mass., p. 98, fig. 404, 1870. 



Verrill, Invert. Anira. Vineyard Sd., p. 686, pi. 29, fig. 212, 1874. 



A number of valves occurred in 2V to 80 fathoms. 



Lucina nassula Conrad. 



Amer. Journ. ScL, vol. ii, p. 394, 1846. 



Proc. Acad. Nat. Sci. Phil., vol. iii, p. 24, 1846. 



Rather common in 7 to 48 fathoms. 

 Lucina trisulcata Conrad. 



Amer. Journ. Sci., vol. xli, p. 346. 



FossQs Tertiary Form. U. S., p. 71, pi. 40, fig. 0, 1838. 



A single valve (No. 40,598) occurred at station 2290, in 10 fathoms. 

 Cryptodon obesus Verriu. 



Invert. Anlra. Vineyard Sd., p. 393, pi. 29, fig. 214, 1874; these Transactions, 

 vol. v, p. r)69, 1882. 



A few valves were found in 15 to 48 fathoms. 



