196 BULLETIN OF THE 



Polycheles 1 tanneri, sp. nov. 



Orbital sinus rounded at the bottom, outer margin spinulose. Median carina 

 of carapace furnished with two anterior rostral spines, followed by five (or six) 

 spines in front of the cervical groove, the fourth (or fifth) of which is double. 

 The arrangement of these spines may be thus formulated: 2. 1. 1. 1. 1. 2. 1 (or, 

 2. 1. 1. 1. 2. 1). Back of the cervical groove the spines of the median carina are 

 2. 2. 2. Marginal spines of carapace arranged as follows : 5 — 3 — 13 or 14). 

 A longitudinal row of four small spinules on the anterior division of the 

 carapace midway between the median and marginal rows, and a row of twelve 

 or fifteen on the branchial regions inside the margin of the carapace. There 

 are, besides, two or three spines on each side of the hind margin of tbe cara- 

 pace, and a few along the cervical groove. 



Resembles P. nanus (Smith), but differs in tbe number of spines on the 

 median and sublateral carinas of the carapace, in the existence of a spine on 

 the antero-external angle of the first and second abdominal pleurae, and in tbe 

 greater number of spines on the merus, carpus, and propodus of the chelipeds. 

 P. nanus, moreover, is described as having tbe posterior pair of thoracic ap- 

 pendages chelate in the male, while in the males of P. tanneri that I bave 

 examined these appendages are simple. Compared with the types of P. agassizii 

 (A. M. Edw.), the carapace of the present species is broader and fewer-spined 

 on the margins; the first and second abdominal pleurae are armed with an 

 anterior lateral spine ; the rostral spine is double ; and the orbital sinus is 

 broad and rounded at the bottom. P. agassizii, like P. tanneri, has non-chelate 

 posterior legs in the male. 



Station 3354. 322 fathoms. 1 male. 



" 3402. 421 " 2 males, 1 female. 



" 3403. 384 " 12 males, 14 females. 



" 3409. 327 " 1 female. 



Polycheles sculptus pacificus, subsp. nov. 



Differs from the Atlantic P. sculptus Smith as follows. The carapace is 

 broader in proportion to the breadth of the abdomen, the lateral margins con- 

 verging strongly at the posterior end, where, in P. sculptus, they continue 

 nearly parallel to one another ; there is a small spine on each branchial region 

 inside of and on a level with the second spine of the submarginal carina, which 

 spine is entirely wanting in P. sculptus; the spine on the anterior border of 

 the ophthalmic lobe is larger and blunter ; the pleurae of the second abdominal 

 somite have a different shape, their anterior margins being in line with the an- 

 terior margin of the tergum, whereas in P. sculptus they form a strong obtuse 

 angle with that margin. 



1 The genus Polycheles, as here defined, comprehends Polycheles, Pentacheles, and 

 Stereomastis of Bate. 



