﻿I.AMPSII.IS 



69 



Extremely close to L. hydiana on the one hand and L. clai- 

 bornensis on the other. It is a rather larger, less inflated spe- 

 cies than hydiana; it is generally thinner and less rayed than 

 that species. The ground color is more yellowish or tawny 

 than in hydiana and the nacre duller and more often blotched. 

 All the specimens I have seen have the beaks so badly eroded 

 that no sculpture is visible. The Unio aMnis of Lea is shaped 

 a little differently from approxima and in the Synopsis I con- 

 sidered it a distinct species. Since writing that I have seen 

 additional material that leads me to regard them both as the 

 same. 



IvAMrsiijs coNTRARiA (Conrad). 



Shell rather small ; valves convex, solid, elliptical ; beaks not 

 prominent, the sculpture not seen; surface generally smooth 

 and shining; epidermis deep ochraceous, becoming lighter at 

 the border of the shell, with linear, radiating wrinkles in the 

 umbonal region ; hinge line regularly curved ; pseudocardinals 

 triangular, solid, low, laterals reversed in the type, but normal 

 in specimens seen; nacre pale flesh-color; muscle scars well 

 impressed, small. The male shell is elliptical or elliptic oval, 

 having a rounded point just above the posterior base; the fe- 

 male is nearly regularly rounded and wider behind ; marsupial 

 swelling rounded and but slightly produced. 



Length (male) 50, height 32, diam. 25 mm. 



Length (female) 52, height 35, diam. 25 mm. 



Type locality, Ogeechee River, Georgia. Also Pine Barren 

 Creek, Escambia county, Florida. 

 Unio contrarins Conrad, Pr. Ac. Nat. Sci. Phila., IV, 1849, p. 



153 ; Jl. Ac. Nat. Sci. Phila., I, 1850, p. 276, pi. xxxvii, fig. 7. 

 Latnpsilis contrarins Simpson, Syn., 1900, p. 537. 



A species close to L. claibornensis and possibly only a variety 

 of it. It is considerably smaller than that species, is more 

 evenly convex, the posterior point of the male shell is nearer 

 the base than is that of L. claibornensis, the pseudocardinals 

 are shorter and more stumpy. Since the Synopsis was written 

 I have examined shells from Pine Barren Creek, Escambia 



