THE VOYAGE OF H.M.S. CHALLENGER. 



provided with well-developed natatory exopodites. Five pairs of pleopoda present 

 in male, as in the Cumidse. Uropoda with both branches biarticulate. Telson 



wanting. 



1 Vaunthompsonia, Sp. Bate. 



Genera. 

 I 



2. Lepfocuma, G. O. Sars. 



3. Lampropid^. 



Integuments thin, squamous. Form of body generally very slender; tail in both 

 sexes cylindrical, without any epimeral plates. Eye present or wanting. Antennulse 

 with both flagella well developed and nearly equal. Antennae in male with flagellum 

 composed of numerous short articulations. Mandibles well developed. Epipodite of 

 maxillipeds comparatively short, with but few, digitiform gill-lobules ; terminal plate 

 of exopodite only slightly indurated. Second pair of gnathopoda rather slender, pedi- 

 form. The two anterior 23airs or only the first pair of legs in female, and all but the last 

 in male, with well-developed natatory exopodites. Only three pairs of pleopoda present 

 in male, or all wanting as in female. Uropoda with the branches very slender, inner tri- 

 articulate, outer biarticulate. Telson distinctly defined, more or less laminar, with three 

 or more terminal spines. 



Genera. 



1. Lamprops, G. 0. Sars. 



2. Hemilampwps, G. 0. Sars. 



3. Paralampraps, n. gen. 



4. Platijasph, G. O. Sars. 



5. Chalarostylis, Norman. 



4. Leuconid.e. 



Integuments very thin and pellucid, smooth. Form of body generally slender, with 

 tail very elongate and mobile, not sharply defined from trunk. Eye always qiiite 

 wanting. Antennulse with one of the flagella small, uniarticulate. Antennae in male 

 with flagellum composed of numerous short articulations. Mandibles rather small, with 

 the body exserted into two angular processes ; anterior branch short, wanting the usual 

 series of lateral spines, molar tubercle very massive. Palp of first pair of maxillso with 

 a single terminal bristle. Epipodite of maxillipeds comparatively small, with but few 

 digitiform gill-lobules ; terminal plate of exopodite membranous, exserted into a narrow 

 flap. Second pair of gnathopoda rather short, with some of the bristles issuing from the 

 outer edge very strongly developed. The three anterior pairs of legs in female, and all 

 but the last in male, with well-developed natatory exopodites. Second pair of legs only 



