POLYCHELES TANNERI. 119 



in W. leptodadijh, then Willemoesia would become a sjnonyine of Foi//ckcks 

 Heller {type, P. typhlops), and Poli/cheles of this memoir would become Pen- 

 tacheks Bate, with P. cuthrix as its typical species. 



Polycheles tanneri Fax. 



Plate XXXI. 

 Bull. Mus. Comp. Zool., XXIV. 196, 1S93. 



Surface of shell pubescent. Carapace broadest at the middle, narrow- 

 ing anteriorly and posteriorly. Orbital sinus rounded at the posterior end, 

 outer margin spinulose. Ophthalmic lobes armed with an anterior spine. 

 Basal segment of antennules furnished with two external spines. Median 

 carina of the 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. This arrangement of spines may be formulated thus : 

 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 the carapace are thus 

 arranged : five on each side of anterior part, three on the middle, and thir- 

 teen or fourteen on the posterior (5 — 3 — 13 or 14). There is a longitudi- 

 nal row of four small spinules on the anterior division of the carapace 

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

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

 are also two or three spines on each side of the hind margin of the carapace 

 and a few along the cervical groove. The first five somites of the abdomen 

 are carinated dorsally, the carina projecting forward on each segment in 

 the form of a spine ; on the sixth segment the carina is double and denticu- 

 late. The base of the telson is adorned with a short denticulated crest. The 

 pleurae of the first and second abdominal segments are armed with a spine 

 at the antero-external angle, and the margins of the third, fourth, and fifth 

 pleurae are slightly denticulated ; there is a granulated crescentic ridge on the 

 outer face of the third, fourth, and fifth pleurae. The upper and lower edges 

 of the merus of the chelipeds are armed with from five to seven spinules ; 

 tlie carpus is short, furnished with three to five spinules on the upper border 

 and with one below at the articulation with the propodite ; basal portion of 

 propodite spinulose on both upper and lower margins. The terminal joint 

 of the posterior pair of thoracic legs is chelate in the mature female, sub- 

 chelate in the young female, simple in the males that I have examined. 



