VENUS ALVEATA. 



DESCRIPTION. 



Shell ventricose; valves very thick, subtriangular, cor- 

 date, with eight remarkably thick, very prominent, much 

 recurved, transverse approximate ribs, of an uniform 

 thickness throughout, terminating abruptly at their an- 

 terior slope, which is much impressed; lunule cordate, 

 included by an impressed line. 



SYNONYMS. 



Venus alveata, Conrad. Jour. Acad. Nat. Sc, vol. vi. 



p. 264, pi. xi., fig. 14, 15. 

 Venus paphia? Lam. Anim. sans. Vert., vol. v. p. 608. 



OBSERVATIONS. 



For an opportunity of examining this interesting spe- 

 cies I am indebted to Dr. Ravenel, who informs me that 

 he obtained it on Sullivan's Island, near Charleston, S. C. 

 It differs from V. paphia, Linn., in not having the ribs 

 abruptly smaller before they reach the anterior slope; 

 and it does not agree with the figure in the Encyc. Meth. 

 of V. fasciata. Although probably recent, the specimen 

 has very much the appearance of a fossil, and this cir- 

 cumstance, combined with its character, leads me to 

 believe that it is the V. paphia, Lam., but certainly not 

 that of Linne.* 



REFERENCE TO THE PLATE. 



Three views of the shell. 

 PI. 63. 



* Having examined the specimens sent to Mr. Say, I find them to 

 bo fossil shells. The si)ccies is characteristic of the Older Pliocene 

 formation, and occurs at Wilmington, N. C. ; St. Mary's river, Mary- 

 land; and City Point, Virginia. — £d. 



