66 G. 0. SARS. CRUSTACEA. [NORW. POL. EXP. 



conspicuously larger than those immediately adjacent to it. The antennae are 

 clothed anteriorly with delicate bristles of somewhat unequal length. 



The posterior antenna? (fig. 5) have the inner ramus comparatively short, 

 scarcely exceeding half the length of the outer, which is distinctly 7-articulate. 



The mandibles (fig. 6) are rather strong, with the masticatory part 

 greatly expanded, and the cutting teeth well developed. The palp is of 

 moderate size, and highly characterised by the poor development of the inner 

 ramus, which is extremely small, and has the terminal setae unusually short 

 in proportion to those of the outer ramus. 



The maxillae (fig. 7), on the whole, resemble in structure those in the 

 genus Undeuchceta. 



The anterior maxillipeds (fig. 8) are likewise constructed upon the same 

 type as in that genus; but all the setae springing from the digitiform lobes 

 are of equal structure, none of them assuming a spiniform character. 



The posterior maxillipeds (fig. 9) are rather slender and doubly geniculate, 

 the 2 basal joints forming with each other a more or less pronounced elbow- 

 shaped flexure, whereas the terminal part is bent in the opposite direction, 

 or reflexed. The latter is about half the length of the 2nd basal joint, 5-artic- 

 ulate, and densely clothed with slender setae. 



The natatory legs (figs. 10 12) are built upon the same type as in the 

 Calanoids described in the preceding pages. They are, however, less power- 

 ful than in Undeuchceta, with the outer ramus less dilated. In the 1st pair 

 (fig. 10) this ramus is distinctly 3-articulate, the 1st joint being well defined, 

 and provided outside with the usual spine. The inner ramus, both in this 

 and the 2nd pair (fig. 11), is uniarticulate, though in the latter pair there is a 

 very slight indication of the separation of a short proximal joint. In the 2 

 posterior pairs (fig. 12) this ramus is, as usual, 3-articulate ; but the boun- 

 dary between the 2 proximal joints is far from being distinct. The last pair 

 of legs, as in Undeuchceta, are wholly absent. 



The adult male is rather smaller than the female, scarcely exceeding 

 a length of 3 mm., and is easily recognizable by the much more slender tail, 

 and the dense clothing of sensory filaments on the anterior antennae. 



The oral parts are much reduced, excepting the mandibular palps and 

 the posterior maxillipeds, the former (fig. 4) having the inner ramus less 



