POLYCHELES TANNERI. 119 
in W. leptoductyla, then Willemoesia would become a synonyme of Polycheles 
Heller (type, P. ¢yphiops), and Polycheles of this memoir would become Pen- 
lacheles Bate, with P. eulhrix as its typical species. 
Polycheles tanneri Fax. 
Plate XXX. 
Bull. Mus. Comp. Zodl., XXIV. 196, 1893. 
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— 15 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 spme; on the sixth segment the carina is double and denticu- 
late. The base of the telson is adorned with a short denticulated crest. The 
pleurse 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 
pleure are slightly denticulated ; there is a granulated crescentic ridge on the 
outer face of the third, fourth, and fifth pleuree. The upper and lower edges 
of the merus of the chelipeds are armed with from five to seven spinules ; 
the carpus is short, furnished with three to five spimules 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. 
