CRUSTACEA MALACOSTRACA. II. I2 c 



or somewhat rounded angles and both ends of each segment are straight. Third, fourth, fifth and 

 sixth segments subequal in length, while second and seventh segments are somewhat shorter. No 

 ventral processes are found. — Thoracic legs (figs. 4b and 4c) moderately short, and all subequal in 

 length and moderately slender; the relative length of the joint almost as in P.instgnis, but the spines 

 on the anterior pairs are much shorter than in that species. 



Abdomen very short (fig. 4a). Five anterior segments combined scarcely as long as and con- 

 siderably narrower than seventh thoracic segment (fig. 4d). Sixth segment about as long as the four 

 preceding segments combined and somewhat broader than the fifth segment; each half of its posterior 

 margin is considerably concave, as the median third of the segment is produced backwards in a 

 triangle with the end nearly acute. — Uropods robust and somewhat shorter than the sixth segment; 

 the peduncle longer than deep (fig. 4 c), with the outer distal angle a little produced as a small rudi- 

 ment of an exopod not marked off; the endopod unjointed, slightly longer than the peduncle. 



Length of the largest specimen 1.9 mm . 



Remarks. I'.subtilis is easily distinguished from all other Tanaidse with four-jointed anten- 

 nulae described in this paper by its uropods. The antennulse are unusually thick and shaped as in 

 subadult males of allied forms, but as no pleopods are found the specimens must be females. 



Occurrence. Taken by the "Ingolf' at a single station. 



Davis vStrait: St. 32: Lat. 66° 35' N., Long. 56°38' W., 318 fm„ temp. 3.9°; 7 spec. 



78. Paranarthrura clavipes n. sp. 

 (PI. XII, figs. 5 a- 5 c) 



Immature Male and juvenile Specimen. Body, seen from above (fig. 5a), moderately 

 slender, broadest across the carapace and tapering much backwards to the abdomen. — Carapace large 

 (fig. 5 a), somewhat shorter than the two following segments combined — which are uncommonly 

 long — , somewhat longer than broad and broadest a little before the middle, which is nearly more 

 than twice as broad as the front end, and consequently the lateral margins are very convex. 



Antennulse (fig. 5b) much shorter than the carapace. First joint a little longer than the three 

 other joints combined and in the immature male two and a half times as long as deep; second joint 

 somewhat produced above and not half as long as the first joint; third joint quite short; fourth joint 

 considerably shorter than the second. Antenna? of moderate length; the joint composed by the 



fusion of fourth and fifth joints is very long, while the penultimate joint is unusually short. 



Chelipeds (fig. 5 b) moderately strong. The basal joint is considerably longer than deep, 

 posteriorly produced in a protuberance which is narrowly rounded behind, and the distance between 

 its end and the front lower angle of second thoracic segment is a little more than half as long as the 

 joint itself. Carpus slightly more than half as long again as the basal joint, somewhat more than 

 twice as long as deep, with the upper basal part somewhat produced backwards ; most of the upper 

 margin and nearly the whole free lower margin are straight and slightly converging. Chela slightly 

 longer than the carpus, almost two and a half times as long as broad, regularly shaped with the 

 fingers acute; the posterior margin almost straight with a single seta; the movable finger slightly 

 shorter than the anterior margin of the hand. 



