80 . 



47. Platy cyclops af finis, 0. 0. Sara. 



(EM. XLIX). 



. Cyclops affinis, G. O. Sars, 1. c., p. 47. 

 Syn- Cyclops pygmceus, Eehberg. 



Specific Characters. Female. Body somewhat less robust than in the 

 preceding species, with the anterior division comparatively narrower. Cephalic 

 segment considerably exceeding in length the 4 succeeding segments combined, 

 and narrowly rounded in front. Last trunk-segment with the lateral parts 

 slightly produced and clothed at the edge with slender recurved spinules. Tail 

 about equalling in length 2 / 3 of the anterior division, and slightly tapered distally; 

 genital segment about as long as the 2 succeeding segments combined, and some- 

 what dilated at the base, last segment more fully developed than in P. phaleratus, 

 though smaller than the penultimate segment. Caudal rami resembling in shape 

 those in that species, but a little more produced; seta of outer edge very small, 

 and attached near the end somewhat dorsally; upper face crossed by a row of 

 small spikes extending from the said seta obliquely anteriorly; middle apical 

 setae strong and minutely denticulated for some part of their length, the inner 

 one about twice as long as the outer, and equalling about half the length of the 

 body ; seta of inner corner very small, shorter than the spine of the outer. 

 Anterior antennae shorter than the cephalic segment, and, as in the preceding 

 species, not much dilated in their proximal part, being composed of 11 joints 

 clothed with short, simple setae. Posterior antennae far less robust than in 

 P. phaleratus, with all the joints well defined. Maxillipeds resembling in struc- 

 ture those in that species; the posterior ones, however, wanting the spinulose 

 ledge of the middle joint. Natatory legs with the basal part less broad and the 

 rami less coarsely spinulose outside; 2nd basal joint in 1st pair obtusely produced 

 at the inner corner, with the deflexed spine rather slender, terminal joint of 

 outer ramus in 1st and 2nd pairs with 3 spines outside, in 3rd and 4th pairs 

 with only 2 such spines; apical spine of inner ramus in 1st pair rather coarse; 

 those in 4th pairs, as in the preceding species very unequal, the inner one 

 being more than twice as long as the outer and conspicuously bent inwards; 

 middle joint of same ramus with only a single seta inside. Last pair of legs 

 well defined, each forming a small sub- quadrangular lamella carrying inside a 

 very slender denticulated spine, outside a seta of about same length, and in the 

 middle another much smaller seta. Ovisacs comparatively smaller than in the 

 preceding species and containing only a limited number of ova. Seminal recep- 

 tacle less broad. 



