14 POST-TLEIOCENE FOSSILS. 



Genus, AVICULA.— Brug. 



A Y I C U L A A T L A N T I C A . 

 Plate III. Fig. 1. 



Avicula atlantica, Lam., An. sans Vert., 2d Ed., Vol. 7, p. 99. 

 Avicula atlantica, De Kay, Zool. New- York, Art. Mollusca, p. 175. 

 Avicula atlantica, L. R. Gibbes, Tuomey's Geol. So. Ca., appendix, p. xxii. 

 Avicula hirudo, Saij, Jour. Acad. Nat. Sci., Phil., Vol. 2, p. 262. 

 Avicula hirudo, Say, Conch. United States, (Binney,) p. 90. 



Description. Shell inequivalve, inequilateral, pearly; obliquely rounded, and striated ; 

 concentric lines of grovi^th w^rinkled. 



This is a rare fossil in the Post-Pleiocene, though quite common on the sea coast of 

 South-Carolina, and often taken alive; the auricles of the fossil are much shorter than in 

 the recent shell, but the descriptions correspond. 



Plate III. Fig. 1, Fossil, natural size. 



Locality. Abbapoola, and Doctor's Swamp, John's Island. 



Museum, College of Charleston ; Cabinet F. S. H. 



Genus, PINNA.— Linn. 



PINNA S E M I N U D A , 

 Pl.we III. Fig. 2. 



Pinna seminuda, Lam., An. sans Vert., Vol 7, p. 6L 



Pinna seminuda, DeKay, Zool. New- York, Art. Mollusca, p. 187. 



Pinna seminuda, Ravenel, Cat. Coll. Shells, p. 7. 



Pinna seminuda, L. R. Gibbes, Tuomey's Geol. So. Ca., appendix, p. xxii. 



Description. Shell thin; surface longitudinally furrowed; furrows wide, gradually 

 contracting towards the beaks ; ridges between the furrows, six to eight, armed with large 

 erect scales on the buccal side of the valves, and extending obliquely to the middle of the 



