Boone, Crustacea, Cruise of "Alva," 1931 203 



tooth on the proximal outer lateral margin, the remainder of this 

 margin nearlj^ straight, crenulate, and terminating distaliy in an 

 acute tooth, which extends beyond the convex distal border of the 

 remaining portion of the blade ; the inner lateral margin is con- 

 vex ; the scaphocerite attains its greatest width about two-fifths 

 of the length from the base. 



The chelipeds are subequal, with the propodal articles approxi- 

 mately two-thirds as long as the carapace, slender, subcylindrical, 

 moderately dilated on the proximal two-thirds, narrowed distaliy 

 and dorsoventrally ; compressed distaliy, with the distal margin 

 thin, oblique; a small, acute, out-jutting finger, which projects 

 beyond the hinged finger. The distal margin of the propodus is 

 widely curved, laminate. The hinged finger is slender, rounded, 

 compressed, distaliy acuminate and bowed or curved to fit closely 

 upon that of the thumb. 



The second pair of legs is weakly chelate. 



The third pair of legs is monodactyl, exceedingly slender, 

 ending in a stylet-like dactyl. 



The fourth and fifth pairs of legs are similar, each definitely 

 thicker than the third pair of legs. 



The present specimen is a female, carrying about fifteen large, 

 rather ovoidal eggs attached to the long cilia of the pleopoda. 

 These eggs are quite well developed, the embryos showing subcir- 

 cular eye-spots, also the segmentation of the abdomen, which is 

 coiled beneath the carapace. 



This species, which is superficially like Pontophilus japonicus 

 Doflein, is rendered distinct by the different number and arrange- 

 ment of carinae on the carapace; the present species having, in 

 addition to the three-spined median carina, six pairs of lateral 

 carinae, three pairs of these being short, oblique, the remaining 

 three pairs being, respectively, one pair two-thirds the length of 

 the carapace, while the two outer pairs each extend the full length 

 of the carapace. The present species also has a strong lateral tooth 

 proximally on the outer margin of the scaphocerite. P. japonicus 

 has none here. 



This species is dedicated to the collector, Mr. William K. 

 Vanderbilt. 



