SOME BLIND GEXEEA 325 



with eyes well developed, and the first and second antennge 

 four-jointed apparently in the male as well as in the 

 female. The male is thought to be distinguished chiefly 

 by a more elongate pleon. The single species is repre- 

 sented by one small specimen supposed to come from 

 2,050 fathoms in Mid Pacific, and other specimens from 

 between 2 and 10 fathoms at Port Jackson in Australia. 



Tanaella, Norman and Stebbing, 1886, has no eyes 

 and no distinct ocular lobes. There are no pleopods in 

 the female, and the uropods are simple, the single branch 

 being also single-jointed. The male is unknown. 



Strong ylura, Sars, 1880, has no eyes and no distinct 

 ocular lobes. The mandibles have the molar moderately 

 large, laminar. There are no pleopods in the female. In 

 the uropods the inner branch is two-jointed, the outer 

 one-jointed. 



Cryptocope, Sars, 1880, like several of the preceding 

 genera is without eyes. The mandibles have the molar 

 sublaminar, unarmed, and on the right hand mandible 

 there is a very prominent secondary plate. The segments 

 of the person are divided by deep instrictions. The pleo- 

 pods are well developed in the male, rudimentary in the 

 female. The uropods in the male are long, with three- 

 jointed inner, and two-jointed outer, branch ; in the 

 female short, with two-jointed inner, and one-jointed outer, 

 branch. 



Haplocope, Sars, 1880, agrees nearly with the preced- 

 ing genus, except that the mandibles have a cylindrical 

 molar, of which the truncate apex is encircled with teeth, 

 and the uropods are moderately long with unequal two- 

 jointed branches. 



Anarthrtira, Sars, 1880, is distinguished from all the 

 foregoing genera by having the pleon unsegmented. There 

 are no eyes. The hands of the first gnathopods are weak. 

 There are no pleopods. In the uropods the outer branch 

 is represented by a conical process not disunited from the 

 peduncle, the inner branch is two-jointed. 



Among the earlier authorities on this family the writ- 

 ings of Kroyer, Lilljeborg, and Fritz Mil Her may be men- 



