142 TANAIDJJ. 



little longer than the fourth, but about the same length 

 as the sixth, while the seventh is about half the length 

 of the sixth. 



The pleon has the first five segments subequal, but the 

 sixth or terminal is quite as long as two of the preceding, 

 and terminates in a central point that is furnished with 

 a solitary hair upon each side of the apex. 



The eyes are small and not easily recognized. The 

 antennae are short, the superior being more robust and 

 slightly longer than the inferior, and tipped with a few 

 cilia ; in length they equal that of the cephalon and first 

 joint of the pereion, which being fused together form 

 the head. The superior antenna consists of four joints, 

 that is, a peduncle of three and a uniarticulate flagellum, 

 but which is more slender and longer than the last joint 

 of the peduncle. The inferior antenna appears to ter- 

 minate in a similar uniarticulate flagellum. The first pair 

 of gnathopoda are long and robust, of which the hand is 

 not larger than the rest of the limb. The carpus is as 

 long as the propodos, and the dactylos is long, curved, 

 and slender, forming with the digital process of the 

 propodos, against which when closed it impinges closely 

 through its entire length, a sharply-pointed and somewhat 

 elongate chela. The second pair has the dactylos long 

 and slender, being hair-like at its extremity and slightly 

 curved ; the remaining pairs of legs, the true pereiopoda 

 or walking legs, are subequal in length, of somewhat 

 slender and feeble proportions, and terminate in small 

 curved dactyla. The five anterior pairs of pleopoda are 

 pedunculated and liberally ciliated on the outer and 

 posterior margins. The posterior pleopoda are biramose, 

 the inner branch being rather shorter than the ultimate 

 segment of the pleon j it is single-jointed, but furnished 

 near the middle, on the inner side, with a small pro- 



