50 POST-PLEIOCENE FOSSILS. 



Genus, ABRA. — Leach. 



ABE A ^QUALIS. 

 Plate VIII. Fig. 7. 



Amphiclesma sequalis, Say, Jour. Acad. Nat. Sci., Vol. 2, p. 307. 



Amphidesma sequalis, Con., Foss. Ter. Form., p. 76, pi. 43, fig. 9. 



Amphidesma sequalis, d'Orb., Prod, de Paleontologie, Vol. 3, p. 101, No. 1886. 



Ampliidesma sequale. Say, Am. Conch., pi. 28. 



Amphidesma sequale, Ravenel, Cat Coll. Shells, p. 3. 



Amphidesma sequalis, L. R. Gibbes, Tuomey's Geol. So. Ca., appendix, p. xxii. 



Amphidesma sequalis, Tuomey 4" Holmes, Pleiocene- Foss. So. Ca., p. 93, pi. 23, fig. 3. 



Amphidesma sequalis, Say's Conch. U. S., (Binney,) pp. 100, 182. 



Description. Shell obliquely-orbicular, ventricose, smooth; beaks sub-medial, nearest 

 to anal end ; umbonial slope sub-marginal, slightly carinated ; anal side somewhat 

 warped or bent. 



This is a recent species on the shores of South-Carolina, Florida, and Alabama, and 

 fossil in the Post-Pleiocene of this State. — T. Sf H. 



Plate VIII. Fig. 7, Natural size. 



Locality. Simmons'. Museum, College of Charleston. 



ABRA A N G U L A T A . — {New Species.) 

 Plate VIII. Fig. 8. 



Description. Shell sub-orbicular, equivalve, sub-equilateral, convex, anteriorly 

 'rounded, posteriorly angulated towards basal margin; anal side with a raised line or 

 warped ridge, extending from beak to angle of margin; surface minutely and concentri- 

 cally wrinkled ; wrinkles distinct towards basal margins, but sometimes obsolete on 

 umbones ; beaks distinct, somewhat acute ; within radiately striated ; strise often obsolete, 

 or not visible but with the aid of a lens, terminating at basal margin ; gives it a finely 

 serrated appearance; pallial impression distinct; lunule deep and broad, distant from 

 margin, projecting up into the middle of the cavity; primary teeth two in each valve, no 

 lateral teeth, but anterior margin of right valve has a projecting rim or elevated edge, 

 which extends from the beak half way down to basal margin ; ligamental-cavity sub- 



