CYCLOPS. 97 



middle line, but rather to one side, and I have myself 

 confirmed this observation. The point, however, 

 which most clearly marks out the genus as distinct, is 

 the peculiar structure of the lower foot-jaw, which is 

 only 4-jointed, and terminates in two remarkable 

 hooked claws. 



Genus 4. Cyclops, Milller (1776). 



Body expanded in front, attenuated behind, com- 

 posed in the male of ten, in the female of nine seg- 

 ments. Head anchylosed with the first thoracic seg- 

 ment. Both anterior antennae, in the male, forming 

 powerful hinged clasping organs, shorter than the 

 cephalothorax. Posterior antennae unbranched, 4- 

 jointed. Mandible dilated and toothed at the extremity; 

 palp reduced to a small tubercle, which bears two 

 branchial filaments. Maxillary palp obsolete ; maxillae 

 themselves conical and bearing several strong, curved, 

 apical teeth, and marginal setae. First pair of foot-jaws 

 slender, armed with several long marginal spines and 

 setae, 4-jointed. Second pair much more robust, some- 

 what like the first pair in the Calanidae; third joint 

 forming a broad laminar process, armed on the 

 margin with powerful claws ; the smaller apical joint 

 bearing in like manner two slender claws and 

 setae. First four pairs of swimming feet 2-branched, 

 both branches 3- jointed. Fifth pair rudimentary, 

 composed of not more than three joints. One eye. 

 Two ovisacs. 



