of the Pacific Shores of North America. 449 



DECAPODA BRACHYURA. 



Tribe OXYRHYNCHA. 



CHIONCECETES BEHRINGIANUS. Stimpson. 

 Chionoecetes Behringianus, Stimpson ; Proc. Bost. Soc. Nat. Hist. vi. 84. 



Carapax with numerous scattered unequal rugose prom- 

 inences which are blunt and wart-like about the middle, but 

 become more acute anteriorly and at the sides. Superior 

 surface covered with a short pubescence. The broad chan- 

 nels above the postero-lateral margins are nearly smooth, 

 but their double margins are granulated. The inferior an- 

 terolateral margin is armed with about fourteen small bifid 

 teeth which diminish in size forwards. The feet are every- 

 where slightly pubescent, with the third articles scabrous or 

 echinulate above ; those of the first pair are muricated along 

 the angles, and everywhere somewhat scabrous on their 

 upper surfaces. The abdomen in the male is one third the 

 width of the sternal plastron at its penultimate article, the 

 infero-lateral angles of which are somewhat produced and 

 tumid. Length of the carapax, 2.5 ; width, 2.52 inch. 



This species may be distinguished from C. opilio, Kroyer, 

 judging from the descriptions of that naturalist, by the 

 shorter feet of the male ; — those of the second pair, in the 

 species here described, being not more than twice the length 

 of the carapax, while those of the first pair are not much more 

 than half as long as those of the second. The abdomen 

 consists in both male and female of seven articles, the three 

 nearest the base being strongly granulated. Kroyer, in his 

 diagnosis of the genus, states the number of articles to be 

 six, although O. Fabricius * gives seven as the number in 

 .his Cancer phalangium. 



It inhabits deep water, the specimens described being 



* Fauna Gronlandica, p. 234 ; n. 214. 

 JOURNAL B. S. N. H. 58 



