43 6 -] A r OA' TH AMERICAN IXVER TEBRA TES. 



271 



CCC. Eyes not divided. Uropods with rami. 



No mandibular palp (Cystisomidas). 



racic segments fused. Body with a median dorsal 

 carina; posterior margins of most of the segments 

 dentate. Gnathopods small, complexly subchelate, 



serrate. Attains a length of four inches. Transpar- 

 ent Cystisoma spinosum (Fabr.) A. M. S. 



/>/). Inner ramus of the uropods free. Head very large, 

 tumid, the sides entirely covered by the large eyes. 

 Flagellum of both pairs of antenna? long and multi- 

 articulate in the male, but short and unjointed in 

 the female. Mandibles with a palp (Hyperiid«e). 

 E. Carpal joint of both gnathopods produced distally 



the first. Gnathopods almost naked. Carpus of 

 the first two penropods narrow, the posterior 



