REPORT ON THE CUMACEA. 



sex-articulate. Only two pairs of pleopoda present in male. Uropoda with both 

 branches Particulate and somewhat complanate, inner spinous, outer setose. Telson 

 wanting. 



1. Leucon, Krdyer. 



2. Eudorella, Norman. 



Genera. 



3. Eudorellopsis, G. 0. Sars. 



5. DlASTYLID^E. 



Integuments generally strongly indurated and often armed with spines. Anterior 

 division of body more or less dilated and sharply defined from tail, which is very slender 

 and mobile. Carapace large and vaulted, with a more or less conspicuous rostriform 

 projection in front. Eye present or wanting. Antennulae more or less dissimilar in the 

 two sexes, rather slender, with the flagella unequal, the smaller one (in female) tri- 

 articulate. Antennae in female forming a simple cylindrical stem divided into distinct 

 articulations, in male more or less elongated. Mandibles well developed, anterior branch 

 with a dense series of lateral spines. Epipodite of maxillipeds rather large, gill-lobules 

 arranged in a more or less distinctly spiral manner ; terminal plate of exopodite 

 membranous, triangular. Second pair of gnathopoda with basal joint very large and 

 curved. The two anterior pairs of legs in female, and all but the last in male, with well- 

 developed natatory exopodites. Only two pairs of pleopoda present in male, the 

 posterior pair sometimes imperfectly developed. Uropoda very slender and elongate, 

 outer branch biarticulate, inner bi- or triarticulate and spinous at inner edge. Telson 

 distinctly defined, with the outer part generally narrowed and spinous at the edges, apex 

 with two spines only. 



Genera 

 1. Diastylis, Say. | 2. Leptostylis, G. O. Sars. 



6. PSEUDOCUMID^;. 



Integuments generally thin and squamous. Tail more or less sharply defined from 

 the trunk. Eye present or wanting. Antennulae small, with one of the flagella rudi- 

 mentary. Antennae in male with outer part of peduncle indistinctly biarticulate, 

 flagellum composed of rather elongate and slender articulations. Mandibles not very 

 strong, anterior branch with but few lateral spines. Epipodite of maxillipeds with only 

 slight traces of gilhlobules, terminal plate of exopodite scarcely indurated. The two 



