70 Bulletin 31 70 



ior with two sharply defined radiating ribs, lunuleand escutcheon 

 scarcely defined. 



Type and specimen figured. — Wautubbee, Miss. In Paleont. 

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



Horizon. — St. Maurice Eocene. 



Localities. — Wautubbee, and Newton, Miss. ; Calvin, I^a. 



Species of Leda not well defined, and of uncertain horizo7i. 

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



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



Nucula mucronataQon. non Sow., Jr. Phila. Acad., vol. i, 1848, p. 128, 



pi. 14, fig. 2. 

 Leda vanuxemi Dall, 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. 'ip. Fig. 17. 



Nucula carolinensis 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^. 

 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. \y% 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. 



