﻿I70 LAMPSILIS 



middle of the shell, and a very blunt, posterior point about on 

 the median line. The male shell is not so full at the jjost-basal 

 part, and ends in a blunt i)oint behind midway up from the base. 



Length (male) 53, height 35, diam. 26 mm. 



Length (female) 30, height 22, diam. 13 mm. 



Type legality, Kio Salado, .\e\v Leon, Mexico. Bayou Teche, 

 Louisiana ? 

 Unio saladoensis LiiA. Pr. Ac. N. Sci. I'hila., IV, i860, p. 305; 



Jl, .Ac. N. Sci. Phila., 1\', i860, p. 370, pi. uxv, fig. 195 ; Obs., 



VIII. i860, p. 52, pi. i.xv, f^g. 195. 

 Margaron (Unio) saladoensis Lea, Syn., 1870, p. 62. 

 Lampsilis saladoensis Simpson, Syn., 1900, p. 569. 



At the time I wrote the Synopsis I had not seen an example 

 of this shell. Since then I have examined a small female shell 

 from Mexico, which agrees well with Dr. Lea's description of 

 the above species, and another much larg-er, which is a male and 

 no doubt belongs to the same species, which is said to come 

 from Bayou Teche, Louisiana. The species evidently belongs 

 in the subgenus Proptera but differs to quite a marked degree 

 from all others. It is shorter, and more inflated than any other 

 species in the subgenus, and is remarkable for its peculiar rays 

 and the apparent want of dorsal muscle scars. 



C^roup of Lampsilis itmbrosa. 



Shell solid, inflated, short elliptical, covered with a shining", 

 rather smooth brownish epidermis, which often has microscopic, 

 radiating folds ; beak sculpture excessively faint, being the 

 merest hint at a double loop, with the nacre at the anterior end 

 suddenly thickened ; that o-f the male scarcely differing from 

 the female ; hinge teeth well developed ; pseudocardinals strong ; 

 laterals large, straight, and club-shaped ; nacre whitish or pur- 

 plish. Animal having the inner gills united to the abdomitial 

 sac ; branchiae large ; marsupium occupying the whole outer 

 gills posteriorly, not projecting much below ; palpi large, con- 

 siderably united behind. 



