﻿The Symvoda. 155 



Family EKDIASTYLID^, n. 



This family is distinguished from the restricted Diastylidae by 

 having the inner ramus of the uropods two-jointed. 



BKDIASTYLIS, n. g. 



With the character of the family. 



The species allotted to this genus are E. sculptus, E. insignis, 

 E. abbreviatus, all assigned to Diastylis by Sars in 1871 ; E. fim- 

 briatus (Sars), 1873 ; E. politus (S. I. Smith), 1882 ; E. liorridus 

 (Sars), 1887 ; E. mystacinus (Sars), 1887 ; E. hexaceros (Zimmer) 

 1908 ; and E. argentatus (Caiman), 1912. 



Ekdiastylis hexaceros (Zimmer). 

 1908. Diastylis hexaceros, Zimmer, Deutsch. Tiefsee-Exp., vol. viii. 



p. 187, pi. M, figs. 93-95. 

 1910. D. h., Stebbing, S.A. Crustacea, pt. 5, Annals S.A. Mus. 

 vol. vi., p. 418. 

 I have not myself met with this species, which was taken by the 

 German Expedition outside the Agulhas Bank in a depth of 565 m. 



Family LBUCONID.E. 



1879. Le2tconidcB, G. 0. Sars, Arch. Naturv. Kristian., vol. iii., p. 6, 



vol. iv., p. 74. 

 1900. L., Sars, Crustacea of Norw^ay, vol. iii., p. 28. 



xAll the pedigerous segments distinct ; telson wanting ; eye want- 

 ing ; first antennse with accessory flagellum small; mandibles 

 broad at the base, spines few ; first maxillae with unisetose palp ; 

 branchial leaflets few ; exopods on first four pairs of per^opods in 

 the male and the first three in the female ; two pairs of pleopods 

 in the male ; inner branch of uropods two- jointed. 



To this family are assigned the genera Leucon, Kroyer, 1846; 

 Eiulorella, Norman, 1867 ; Eudorellopsis, Sars, 1882 ; and Pseitdo- 

 leucon, Zimmer, 1903. From it are detached the three genera 

 Paraleucon, Hemileucon, and Heteroleucon, all instituted by Dr. 

 Caiman in 1907. The first of these I take as representative of a 



