89 



rather expanded below, 4tli pair deeply emai'ginated posteriorly and forming 

 below the emargination a sliai'p corner, 5th pair comparatively small and 

 more broad than deep. Last pair of epimeral plates of raetasome with the 

 terminal lobe sharply pointed. First segment of nrosome scarcely imjiressed 

 dorsally. Eyes lageniform, distinctly constricted at the middle and consider- 

 ably dilated below, in male mnch larger than in female ; pigment in both sexes 

 vei'y dark, Ijlack. Snpeiior antennae in female abont the length of the cepha- 

 lun and the 2 first segments of mesosome combined, 1st joint of the pednncle 

 very large; tiagellum somewhat longer than the peduncle and composed of 

 abont 15 joints, the 1st of which is about as long as the 5 succeeding ones 

 combined; accessory appendage more than half the length of the flagellum 

 and S-articnlate, 1st joint the largest. Inferior antennse considerably longer 

 than the superior, antepenultimate joint of the pedimele rather thick and 

 scarcely shorter than the penultimate; flagellum slender aoul composed of 

 about 23 articulations. Anterior gnathopoda strong, propodos longer than the 

 carpus' and nearly of unifonn breadth throughout, palmar edge transversal 

 and defined Ijelow l>y a rightangled corner. Postei'ior gnathopoda with the 

 propodos about half the length of the carjnis and (ival in form. The 2 post- 

 erior pairs of pereiopoda nearly e([ual in lengtli and considerably longer than 

 the 3rd pair. Last pair of urojDoda with the inner ramus somewhat longer 

 than the basal joint of the outer; both rami in male larger than in female. 

 Telson ctblong ipiadrangnlar, only slightly tapering distally, with 2 ])airs of 

 dorsal denticles; cleft extending beyond the middle, and somewhat widening 

 below; terminal lobes f)btuse at the tip, forming exteriorly a projecting angle 

 inside whicli occiu's a small denticle. Colour (in Norwegian specimens) whitish, 

 each segment exhibiting dorsally a transversal j^ellowish band. Usual length 

 of adult female 18 mm.; maximum length of arctic specimens 40 mm. 



BemarJcs. — There cannot, I think, be any doubt that the Cancer nu- 

 (jax of Phipps is the present species, and as that name is much elder than 

 any of the specific appellations proposed by Kroyer, it ought certainly to be 

 retained for the species under consideration. Arctic specimens would seem to 

 differ from those met with off the Norwegian coast, not only by their much 

 larger size and by the above mentioned somewhat different proportion between 

 the carpus and propodos of the anterior gnathopoda, but also by the colour, which, 

 according to a coloured drawing made during the Norwegian North Atlantit^ 

 Exjiedition, is a light claret-red. 



Occurrence. — The species would seem to occur along the whole coast 



' In arctic specimens the cai'inis appears generally larger, being often as long as the pro- 

 podos and much broader. 



