50 POST-PLEIOCENE FOSSILS. 



Genus, ABRA. — Leach. 



ABE A JEQTTALIS. 

 Plate VIII. Fig. 7. 



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



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



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



Amphidesma aaquale, Say, Am. Conch., pi. 28. 



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



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



Amphidesma sequalis, Tuomcy $ Holmes, Pleiocene Foss. So. Ca., p. 93, pi. 23, fig. 3. 



Amphidesma Eequalis, 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. $ H. 



Plate VIII. Fig. 7, Natural size. 



Locality. Simmons'. Museum, College of Charleston.. 



A B R A ANGULATA.- (Sea 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 radiatefy striated; striae 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; lunula, 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 clown to basal margin ; ligamental-cavity sub- 



