﻿i.AMPSiLrs 55 



rounded, ending near the base of the shell in a rounded point ; 

 surface somewhat concentrically sulcate, shining, with a few 

 narrow rays, greenish-yellow ; hinge plate solid ; left valve 

 with two rather strong pseudocardinals, the anterior under 

 the beak, more elongated, stumpy, with two sub-remote later- 

 als, the lower a little the larger ; right valve with one strong 

 pseudocardinal and a small one above it, with an irregular, 

 low tooth under the beak and one high, truncate lateral ; muscle 

 scars well marked, smooth, the jx>sterior ones round ; nacre 

 bluish-wnite, silvery, iridescent behind. 



Length 70, height 46, diam. 26 mm. 



Type locality, Chattanooga (river?), Georgia. xA^lso, Shorter, 

 Alabama. 

 Unio gerhardtii Lea, Pr. Acad. N. Sci. Phila., VL 1862, p. 



168 ; Jl. Ac. N. Sci. Phila., V, 1862, p. 208, pi. xxxi, fig. 277 ; 



Obs., IX, 1863, p. 30, pi. XXXI, fig. 277. 

 Margaron (Unio) gerhardtii Lea, Syn., 1870, p. 35. 

 Lampsilis gerhardtii Simpson, Syn., 1900, p. 532. 



The only specimen I have seen is a male, and I am not pos- 

 itive whether it would be placed here or in the luteola group, 

 as the beaks are too badly eroded to give any indication of the 

 beak sculpture. It has some characters like /,. straminea Con- 

 rad. 



Lampsilis mui.tiradiata (Lea). 



Shell elliptical or subovate, rather solid, somewhat inflated ; 

 ligament long; beaks not prominent, sculptured with rather 

 coarse, irregular, corrugated ridges, which have a tendency to 

 be doubly looped ; posterior ridge low, rounded ; epidermis with 

 very fine, concentric laminae, generally shining, greenish-yel- 

 low with ver)'^ many wavy rays covering the whole shell ; some- 

 times a number of the green rays are blended together ; the 

 umbonal region is generally brownish ; left valve with two 

 rather delicate, elevated, sometimes subcompressed, pseudocar- 

 dinals and two short remote laterals, the inner the higher; 

 hinge line rounded ; right valve with one high pseudocardinal 

 with a small, compressed one above it, and sometimes a vestige 



