232 University of California Publications in Zoology. [Vol.4 _ 



margin, not as long nor so stont as in the female, its lower 

 margin continuons in a slightly cnrved line with that of the 

 segment bearing it ; the ultimate segment snbcylinclrical, slightly 

 arced, a little under one-half of the diameter of the preceding, 

 bearing at its apex an irregular deflected lobe on one side, about 

 one-fifth the length of the first segment of the flagellum and 

 bearing on its lower margin, about one-fifth of its length from 

 the base, a stout spine. Flagellum two-thirds as long as the ulti- 

 mate segment of the peduncle, first segment four times as long 

 as the second, third segment minute, bearing two claws and 

 numerous setae. A very immature male (pi. 9, fig. 7) besides 

 having the antennae much shorter and thicker, and the second 

 segment of the flagellum not in evidence, shows a distinct tooth 

 at the base, within, of the large curved spine of the penultimate 

 segment of the peduncle, and the apical hooks of the flagellum 

 are longer. 



Inner plate of first maxillae nearly obsolete (pi. 9, fig. 9) ; the 

 outer bearing seven simple spines. The palp 2-segmented; the 

 second segment nearly five times as long as the first, bearing on 

 its apex about 16 spines, the apical spine recurved and serrated. 

 Second maxillae margined with a thick fringe of setae (pi. 9, 

 fig. 8). 



First gnathopods with carpus slightly longer and consider- 

 ably, broader than the propodus (pi. 10, fig. 12) ; ischium with 

 an apical row of long setae; merus with a few setae near the 

 apex; carpus thickly fringed behind with setae a little longer 

 than the dactyl, about eight pairs of setae in front and an oblique 

 row of about six setae near the apex; propodus with six trans- 

 verse rows of overlapping setae in front, and a few long setae 

 along the po.sterior margin, oblong, palm slightly receding, emar- 

 ginate mesally, bearing six marginal spines; dactyl longer than 

 the palm, unarmed, a tuft of setae on the propodus at its base 

 in front. 



Second gnathopods (pi. 10, fig. 13) not chelate, with the pos- 

 terior margin of the merus and anterior of the carpus united 

 throughout their entire length ; free margin of merus fringed 

 with two rows of dense setae, about three times the length of the 

 dactyl; front margin of the carpus with a very few long setae; 



