﻿LAMPSILIS 57 



blunt, somewhat drawn out point at the middle of the height 

 of the shell ; the disk is rather smooth, epidermis wrinkled in 

 front and behind, greenish-yellow or brownish, somewhat 

 lurid ; there are a few narrow or hair-like wavy rays, usually 

 arranged in groups ; ligament rather long, scarcely developed 

 in front of the beaks ; left valve with two rather stumpy pseu- 

 docardinals, which are scarcely compressed, placed in front of 

 the beak and two short laterals ; hinge plate narrowed and 

 rounded for a long distance ; right valve with one stumpy 

 pseudocardinal and sometimes a small one above it, with a sin- 

 gle, somewhat truncated lateral behind ; muscle scars well im- 

 pressed, smooth ; nacre dirty bluish-white, lurid in the cavity 

 of the shell. The female shell is but little more inflated in the 

 po'st-basal region than that of the male. Both are somewhat 

 angled a little behind the middle of the base. 



Length 60, height 40, diam. 2^ mm. 



Alabama and Tombigbee drainage. 



Type locality, Etowah River, Ga. 

 Unio doliaris Lka, Pr. Ac. N. Sci. Phila., XVII, 1865, P- 88; 



JI. Ac. N. Sci. Phila., VI, 1868, p. 260, pi. xxxii, fig. 75; 



Obs., XII, 1869, P- 20, pi. XXXII, fig. 75. 

 Margaron (Unio) doliaris Lka, Syn., 1870, p. 42. 

 Lampsilis doliaris Simpson, Syn.. 1900, p. 533. 



The best distinguishing characters of this species are the 

 angulation just behind the center of the base, from which there 

 is an almost straight line to the hinder part of the shell, and the 

 almost beak-like posterior point, which is sometimes slightly 

 biangulate. The clustered rays seem to be a fairly constant 

 character. I am rather doubtful, though, whether it is a valid 

 species. 



Lampsilis BREVicuLA (Call). 



Shell obovate, thin, subcompressed, with a very low, ill-de- 

 fined posterior ridge ; beaks rather low ; ligament long, passing 

 under the beaks and appearing in front in a small lunule ; sur- 

 face nearly smooth, greenish straw-colored, having a smoky 

 tint, with a few delicate, broken rays on the po.sterior half; 



