Boone, Crustacea, Cruises of "Eagle" and " Ara," 1921-28 205 



being marked with heavier longitudinal reticulations. There are a 

 pair of depressions at the outer margin of the urogastric region. 



The orbits are not quite half as long as the interorbital border, with 

 a distinct notch near the inferior outer angle and a wide inner hiatus 

 Avhich is partly filled by the antennal peduncle, and partly by an iso- 

 lated tooth. The eyestalks are cylindrical, with a distinct median con- 

 striction on the outer upper side and a rounded process projecting 

 on the cornea, which is very convex, elliptical, set obliquely terminal. 



The antennulae are set nearly transverse in narrow fossae and are 

 partly concealed by the frontal border. 



The antennal peduncle partly fills the orbital hiatus and has a con- 

 spicuous excretory tubercle on its basal joint; the flagellum is quite 

 small and lies within the orbital hiatus. 



The external maxilliped has a tapering rod-like exognath which is 

 two-thirds as long as the endognath and bears on inner, thread-like 

 flagellum about half as long as the basal rod; the ischium of the en- 

 dognath is subrectangular with its inner margin fringed with setae, as 

 long as the merus, the latter being a trifle wider distally than the 

 ischium, and having its inner distal margin depressed ; the palp arises 

 from the antero-external angle and has an unusually large sublobate 

 first joint which fits upon the distal border of the merus, and has its in- 

 ferior distal margin produced ; the second joint is much smaller but is 

 distinctly three-sided ; the third joint is quite small but thick and armed 

 on its inner surface with a brush of setae. The maxillipeds are set 

 wide apart from each other, showing the mandibles. This space be- 

 tween the maxillipeds at its widest point is one and one-half times as 

 wide as the width of the maxilliped at the distal end of the ischium. 

 The pterygostomian region is finely tometose. The abdominal belt 

 consists of seven segments in both sexes. 



The chelipeds (male) have the coxa produced to a tooth-like process 

 at its outer distal angle ; the basis is small and fused with the ischium ; 

 the latter is produced to a tooth-like process on its distal ventral mar- 

 gin and bears four or more sharp little teeth on its inner ventral mar- 

 gin ; the merus is slightly longer than its distal width, three-sided with 

 all three margins denticulate, the inner ventral one most pronouncedly 

 so; the carpus is short, convex and denticulate on its outer margin, 

 with a large, lanceolate acuminate tooth on its inner marginal angle ; 

 the propodus is high, subovate, convex on its outer surface, with a 

 sharp, flat tooth at the upper distal margin near the propodal finger, 

 with the upper edge of the propodus and half of the finger denticu- 



