OF THE ' SOUTHERN CROSS ' EXPEDITION. 55 



As tlie important characters ia this genus are external, and 

 as it was desirable not to mutilate the single fine specimen, I 

 have not attempted to describe the mouth-organs or Limbs, the 

 latter of which appear to resemble those of U. cornigera (Fabr.). 

 The absence of the acute prolongations of the 4th and 5th side- 

 plates distinguishes it from the Northera species. 



Fam. EusiRiDJ;;. 

 Genus Eusibus, Kroyer, 1845. 



E. LiEVis *, n. sp. (PI. 10. figs. 70-76.) 



One specimen ; no locality given. 



Body compressed, without dorsal teetli or posterior projections. 

 Third segment of metasome with the posterior margin rounded and 

 smooth. 



Head as long as the first two segments, with a short rostrum. 

 Eyes rather small and round. 



Maxillipedes with the dactylus largely developed. 



Upper antennae nearly twice as long as the lower ; first two 

 joints subequal, the 3rd shorter than the 1st joint of the flagel- 

 lum, the distal margin somewhat dentate; secondary appendage 

 about three-fourths the length of the 1st joint of the flagellum. 

 Elagellum 11-jointed, the 1st and 10th joints the longest. 



Lower antennae : peduncle reaching beyond the middle of the 

 2nd joint of the upper antennae. Elagellum 5-jointed. 



Gnathopods of the usual structure in this genus ; the propodos 

 much wider than long ; carpal projection shorter than usual ; the 

 Ist joint of the 1st gnathopods much wider than that of the 2nd 

 pair, otherwise they are alike. 



Eirst and second perseopods about as long as the gnathopods, 

 slender, without spines, and with only a few^ setules ; dactyli 

 strong. 



Eirst joints of the last three pairs of perseopods moderately 

 wide loith smooth margins. 



Telson reaching to the end of the peduncle of the 3rd uropods. 



Length 4 mm. 



This species may be easily distinguished from the other known 

 species by the absence of dorsal teeth on the segments and by 

 the entire margins of the 3rd metasome-segment and the 1st 



* Lcevis, smooth, from the absence of dorsal prolongations and of teeth on 

 the margins uf the 3i'd metasome-segment and 1st joints of perteopods. 



