MAIAD.U. 



they are shorter, and divergent for about one-third of their 

 length, as in the former species. The lateral margin of 

 the carapace is without spines, excepting, in some speci- 

 mens, a very small one on the hepatic region. The supra- 

 orbitar spine is smaller than in the other species, not ex- 

 ceeding one-third the length of the rostrum in the male ; 

 it is directed outwards and forwards ; the post-orbitar 

 spine is very small. The regions of the carapace are very 

 strongly marked and gibbous, particularly the genital and 

 intestinal, and they are separated by deep furrows. There 

 is on each branchial region a strong prominent spine which, 

 with a large round tubercle just above the middle of the 

 posterior margin, on the intestinal region, form an obtuse 

 triangle. The antennae, the pedipalps, and the abdomen, 

 are very similar to those of P. tetraodon. The anterior 

 pair of feet are of moderate size, not nearly so broad and 

 massive as those of the other species, and the hands com- 

 pressed. The remaining feet are tuberculated, excepting 

 the penultimate joint of the second pair, which is without 

 tubercles or spines. The whole surface is covered with a 

 very dense villous coat, much thicker than in P. tetraodon, 

 and there are a few tufts of longer club-shaped hairs inter- 

 spersed, with which also the base of the rostrum and that 

 of the antennas are furnished. 



This species is exceedingly liable to the growth of foreign 

 substances upon the surface, to which the dense villous 

 covering affords a very ready and firm attachment. I have 

 a specimen in my collection the form of which is almost 

 completely concealed by a mass of sponge which has grown 

 on its back. 



Dr. Leach states that it was first noticed by Mr. Gibbs, 

 who was employed as a collector by Montagu. It was 

 described and figured by the latter indefatigable naturalist, 



