PHYLUM ARTHROPODA 



529 



Cyclops (Fig. 416, 1) has been compared in form to a split pear, 

 the broad end being anterior, and the convex surface dorsal, 

 e first thoracic segment is fused with the head, and the 



anl.Z 



CLlt.f 



2 . C a I o 1 c a lanus 



FIG. 41C. la, female Cyclops, from the right side; b, dorsal view; C, antenna of male; 



ID, swimming-foot. aJid.l, first abdominal segment; ant.l, aiitemiule ; ant.%, antenna; 

 c. th. cephalo-thorax ; e. median eye ; en. endopodite ; e.s. egg-sac ; ex. exopodite ; or. ovary ; 

 pr.l, />;.,?, protopodite ; r. rostrum; s.f. swimming -feet ; th.2, th.6, thoracic segments. (After 

 Huxley, Gerstaecker, Hartog, and Giesbrecht.) 



cephalo-thorax (c.tli.) thus formed is covered with a carapace pro- 

 duced in front into a short spine or rostrum (r), near the base 

 of which, on the dorsal surface, is the median eye (e). There are 

 five free thoracic segments : the last (th. 6) bears the genital 

 VOL. I M M 





