28 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 



is amply sufficient to identify them as the two sexes of the same 

 species even though the present locahty is so far removed from the 

 previous ones. Accordingly, one of these males has been selected 

 to serve as the type of its sex and has been given Cat. No. 69865 U. 

 S.N.M. and a description and figures are here given. 



Male. Carapace more than half the entire length and longer 

 than wide, with nearly parallel sides; median posterior lobe half the 

 width of the carapace and scarcely projecting behind the lateral 

 lobes; the latter narrow and rather bluntly rounded. Free segment 

 almost as wide as the genital segment, but much narrowed where it 

 joins the carapace. Genital segment subovate, narrowed to the width 

 of the abdomen posteriorly, with strongly convex sides. Two pairs of 

 leg rudiments on the ventro-lateral margins nearer the posterior end. 

 Abdomen two-segmented, the segments about equal in length and 

 width; caudal rami as wide as long, each armed with 3 stout setae 

 densely plumose. These setae afford excellent anchorage for various 

 symbiotic organisms both vegetable and animal and are often dense- 

 ly tufted with them. 



The appendages are similar to those of the female with these 

 agreements. The stout terminal claw of the maxilliped shuts into a 

 groove on the inner surface of the basal segt, the latter being con- 

 siderablv enlarged. This claw bears on its ventral surface a much 

 larger accessory claw than that of the female, and a second acces- 

 sory claw considerably smaller than the first. The basal segment of 

 the third exopod has a stout flanged spine blunt at its tip, and the 

 second and third segments also have spines along their outer mar- 

 gins. The fourth leg is four-segmented with five spines; the four 

 proximal spines have serrated flanges, the distal spine is without a 

 flange. The proximal spine (on the second segment) has two flanges, 

 the outer one more coarsely toothed than the inner; the next three 

 spines have but a single flange, the size of the teeth diminishing so 

 that those on the flange of the fourth spine are only one fourth as 

 large as those on the first spine. There are rudiments of a fifth and 

 sixth pair of legs on the sides of the genital segment near its poster- 

 ior margin. Each of the fifth pair consists of a small papilla tipped 

 with one long and densely plumose seta and three or four very short 

 ones. Each of the sixth pair is made up of a single medium-sized 

 seta attached directly to the segment with no papilla. 



Total length, 6 mm. Carapace, 3.50 mm. long, 2.95 mm. wide. 



