NO. 1507. 



FRESH- WA TER AMPHIPODA— WECKEL. 



37 



In the female the first g-nathopods have thecarpu.s short, triangular, 

 as broad as the propodus; propodus less than twice as long as In-oad; 

 anterior margin slightly convex; posterior margin straight or nearly 

 so, furnislied with a few fascicles of long hairs; palm slightly oblique 

 and convex, furnished on each side with a few hairs, six or eight 

 short notched spines, and one long stout spine at the tip of the closed 

 dactyl; dactyl stout and curved. In the male, from Hay's descrip- 

 tion, the propodus is larger, st()ut(n% and more strongly armed than 

 in the female. 



Propodus of the second gnathopods of the female elongated, twice 

 as long as broad, narrowed distally; lateral margins slightly convex, 

 the posterior one furnished with a few fascicles of long hairs; palm 



m. 3 



Fig. 6.— NiPHARCius antennatus, female. Ntcka.jack Cave, Shei.lmound, Tennessee. 



oblique, convex, armed as in the first pair, but with more numerous 

 spines. In the male, according to Hay's description, the second 

 g-nathopods are larger than in the female and have the propodus pro- 

 portionall>^ more developed. 



The abdominal segments are rounded above and without spines. 



The uropods project backward about an equal distance; the terminal 

 pair are slightly longer than the peduncle of the second pair, with the 

 outer ramus well developed, composed of two segments, the terminal 

 one very short, and armed distally with a few spines, the first segment 

 furnished on both margins with four or five spines; inner ramus short, 

 rudimentary^ and furnished with a few hairs at the tip. 



