coROPniii)J5. 271 



as the inferior margin. First two pairs of pcroiopoda subequal ; 

 thii-d and fourth subequal, shorter than the preceding ; posterior 

 pair longest. Posterior i)air of pleopoda scarcely reaching beyond 

 the telson. 

 Hab. Tubes built of stone, &c., cemented together. Scandinavia 



This description is dependent upon the correctness of Kroyer's 

 fiffure. 



'O-- 



7. NJENIA, n. g. 



Antennae siibequal ; superior without a secondary appendage ; in- 

 ferior arising posteriorly to the superior. Gnathopoda subchelate ; 

 second pair very large. Pereiopoda strong, subequal. Posterior 

 pair of pleopoda biranious, rami styliform. Telson tubular, tipped 

 ■nith one or two nidimentary denticles. 



This genus differs from Eurystlieus chiefly in the absence of the 

 secondary appendage to the superior antennae and in the larger size 

 of the second pair of gnathopoda. • 



1. Naenia tuberculosa*, n. s. (Plate XLYI. fig. 2.) 



Eyes small, round, red. Superior antennae half as long as the animal, 

 having the first joint stout and as long as the cephalon, second 

 joint longer than the first and much slighter, third shorter than 

 the first and more slender than the second ; flagellum nearly as 

 long as the last two joints of the pcdimcle. Inferior antenna? 

 having the peduncle as long as the peduncle of the superior, last 

 two joints subequal ; flagellum not longer than the last joint of 

 the peduncle. First pair of gnathopoda having the carpus and 

 propodos subequal ; propodos ovate, palm oblique, imperfectly 

 defined; dactylos long, slender, serrated on the inner margin. 

 Second pair of gnathopoda having the carpus short and nearly as 

 broad as the propodos ; propodos long-quadrate, palm receding, 

 tuberculated ; dactylc"? extremely arcuate. First two pairs of 

 pereiopoda ha\4ng the meros long and carpus short ; third pair 

 having the basos excavate infero-posteriorly ; fifth pair longer than 

 the preceding. Posterior pair of pleopoda extending fui-thcr than 

 the preceding. Telson tubular. 



Length ^ths of an inch. 



Ilah. Plymouth, and Ox\\ich Bay, Glamorgan (C. S. B.) ; Tenby 

 {Mr. Webster) ; Banff {Mr. Edivard). 



* The specific names in this genus refer to the character of the palm of the 

 second pair of pnathopoda. 



