﻿NKPHRONMAS 275 



terior point is liigh up on the shell ; it is sharper than that of the 

 male and occurs at the end of a dark ray. 



Length (very large male) 92, height 50, diam. 30 mm. 



Length (male) 62, height 35, diam. 18 mm. 



Length (female) 65. height 40, diam. 23 mm. 



Cuba. 

 Unio ffuudlaclii DrNKKR, Mai. Bliitt., \\ 1858, p. 228. 

 Nephronaias i^Midlachi Simpson, Syn., 1900, p. 505. 

 Unio scamnatns von Martens, Biol. Cent. Am., Moll., 1900, 



P- 507- 



The original description is as follows : "L^. testa ovata, 

 paullo compressa, sulcis striisque subtilibus concentricis in- 

 structa, epidermide tenui fusca, in speciminibus junioribus 

 olivacea, vestita ; umbonibus parum prominentibus decorticalis 

 quartam paene testae partem occupantibus ; margine dorsali 

 leviter curvato, basali plus minusve ventroso ; extremitate an- 

 tica attenuata et rotundata, postica dilatata ; denti'bus cardinal- 

 ibus crassiusculis, lateralibus augustis ; margarita flavescente 

 vel coerulescente, posticimi versms marginem ftavescente. 

 Flumine Taco Taco. Cuiba." 



The statements that this species is only slightly compressed, 

 the dorsal margin is lightly curved, the basal inflated, the an- 

 terior end narrowed and rounded, the posterior dilated, all 

 apply to the shorter, less compressed, paler colored, smoother 

 species, in which the female shell has a most decided marsupial 

 swelling, and they do not apply to what I believe is the Unio 

 scamnatns of Morelet. I have before me a female specimen of 

 what I believe is gwidlachi, which is as decidedly swollen at 

 the post-basal region as is any member of the genus LainpsUis. 



Nephronaias ^ruginosa (Morelet). 



Shell inequilateral, subrhomboid, moderately convex, solid, 

 covered with a yellowish-chestnut epidermis, and having slight 

 concentric sculpture; posterior ridge low, somewhat double, 

 and ending behind in a wide, faint biangulation ; beaks mod- 

 erately elevated, smooth, according to the author of the spe- 

 cies ; left valve with one solid, somewhat ragged pseudocar- 



