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generally clothed on the dorsal face with oblique rows of fine spikes; middle 

 apical setae comparatively strong and rather unequal in length, being minutely 

 denticulated for a good part of their length. Anterior antennae short, with the 

 number of joints more or less reduced. Posterior antennae likewise less slender 

 than in the preceding genera. Both pairs of maxillipeds comparatively short 

 and stout; the posterior ones with the outer 2 joints confluent. Natatory 

 legs with the basal part broad and flattened, the rami 3-articulate and nearly 

 equal in length; middle joint of inner ramus in 1st pair with only a single seta 

 inside ; terminal joint of same ramus in all the pairs comparatively small. Last 

 pair of legs in some cases well defined, each forming a small lamella carrying 2 

 thin setae and inside them a denticulated spine, in other cases replaced on each 

 side by 3 spines only. Seminal receptacle short and broad, not produced behind. 

 Remarks. The present genus answers to the last of the groups of 

 Cyclopses distinguished by Dr. Schmeil, viz., his "phaleratus affinis fimbriatus 

 group". The species belonging to this genus are especially distinguished by the 

 pronouncedly applauated form of the anterior division of the body, which gives 

 them a rather characteristic appearance, and also exerts a certain influence on 

 the movements of the animal. It is indeed -from this character that the generic 

 name here proposed has been derived. In some particulars a certain agreement 

 with the preceding genus Leptocy clops may be found to exist; but in other points 

 the species here under consideration differ so much, that they cannot properly 

 be brought together in the same genus. In addition to the 3 Norwegian species 

 described below, the Cyclops Poppei Rehberg is unquestionably referable to the 

 present genus. This form, it is true, has been considered by Dr. Schmeil as 

 merely a variety of C. fimbriatus Fischer; but in my opinion it ought to be 

 kept apart as a distinct, though nearly allied species. Further, among the 

 several species of Cyclops recorded by the present author from Lake Tanganyika, 

 the 2 forms, (?. oligarthrus and C. compactus are undoubtedly members of the 

 same genus. We know accordingly as yet of 6 different species belonging to 

 the present genus. 



