70 Bulletin 31 70 



ior with two sharply defined radiating ribs, hmuleand escutcheon 

 scarcely defined. 



Type and spccimeyi figured. — Waiitubbee, Miss. In Paleont. 

 Mus. Cornell Univ. (No. 15 a is from Newlon, Aldrich Coll. 



Horizon. — St. Maurice Eocene. 



l.ocalities. — Wautubbee, and Newton, Miss. ; Calvin, La. 



Species of Leda not well defined, and of luicertain horizon. 

 Species from Vanuxem's cabinet, Orangeburg District, S. C. 



Leda vanuxemi Dall, PI. 25. Fig. 16. 



A^ncula mua'0?iataQon. nan Sow., Jr. Phila. Acad., vol. i, 1848, p. 128, 



pi. 14, fig. 2. 

 Leda vaniixenii T)s\\, Trans. Wag., Ill, '95, p. 578. 



Conrad'' s original description.* — Elliptical, convex in the middle, with 

 equal, laminated, not closely arranged lines, about 17 in number; anterior 

 side longest, the end acutely pointed ; a submarginal furrow emarginates 

 the base ; posterior side slightly contracted, end obtusely rounded or sub- 

 truncated. Length 9-10. Height 6 [.6 in. ?] 



Leda carolinensis Conrad, PI. 23. Fig. 17. 



Nucula caroline?isis Con., Jr. Phila Acad., vol. i, p. 128, pi. 14, fig. 3. 



Conrad's original description. — Somewhat elliptical, convex, with 

 rather closely-arranged prominent concentric lines, wanting on the posterior 

 side, which is rather shorter than the anterior and regularly rounded at the 

 end ; anterior submargin with a narrow groove, bounded by a subcarinated 

 line; anterior side narrowed and rather obtuse at the end. Length 5^. 

 Height %. 



Leda subtrigona Conrad, PI. 25. Fig. 18, 



Nucula subtrigona Con., Jr. Phila. Acad., vol. i, 1848, p. 128, pl. 14, 

 fig. 4. 

 Conrad's original description. — Subtriangular, ventricose, nearly 

 equilaterial, with numerous, prominent concentric lines; anterior side 

 pointed, flexuous ; submargin angulated : anterior margin sinuous, end 

 angular ; ligament margin straight, basal margin profoundly rounded. 

 Length 2-3. {}/% Proc. Phila. Acad., '47, p. 297]. Height % nearly. 



Leda calcarensis Conrad, PI. 25. Fig. 19. 



Nucula calcarensis Con., Jr. Phila. Acad., vol. i, 1848, p. 128, pl. 14, 



^Descriptions first published in Proc. Phila. Acad., 1847, p. 297. 



