1871.] MR. G. S. BRADY ON EUROPEAN CYPRIDINIDiE. '291 



laminae being the same in both sexes. The structure is, in fact, en- 

 tirely that of a female Bradycinetus. Further, on examining a spe- 

 cimen of Asterope grcenlandica, Fischer, taken in the same locality, 

 I found that its characters were those of a male Bradycinetus ; and 

 on comparison of the shell with that of B. brenda, the points of 

 resemblance appear so striking that I entertain no doubt of its being 

 the male of that species. And I may here mention that although 

 Sars appears to have found the excessive spinous armature (spines 

 nearly thirty in number) of the vermiform appendage of B. brenda 

 reproduced in "P. longicornis," I have myself never been able to 

 see more than eight or nine spines in the latter species ; while in 

 "A. groenlandica'" they number about thirty as in B. brenda. 

 Adopting these views, the genera of European Cypridinidse may be 

 briefly characterized as follows : — 



Cypridina (M. -Edwards). 



Shell smooth, thin, and flexible ; notch shallow ; its posterior 

 extremity only slightly exserted. Superior antennae seven-jointed ; 

 setae of moderate length ; natatory branch of inferior antenna nine- 

 jointed, bearing moderately long setae ; secondary branch very small, 

 subulate. Basal joint of mandibular feet bearing an entire subcorneal 

 and densely hairy process ; penultimate joint much elongated and 

 beset on the interior margin with numerous ringed setae ; last joint 

 very short and almost obsolete. 



Bradycinetus (G. O. Sars). 



Shell much denser than in Cypridina, punctate ; notch deep. 

 Superior antennae six-jointed ; the apical setae of moderate length, sub- 

 equal, rather longer in the male than in the female ; inferior antennae 

 nearly as in Cypridina ; length of joints nearly alike in both sexes ; 

 filaments very short in female, rather longer in male ; secondary 

 branch of the inferior antenna in the female Particulate, very small, 

 in the male larger and triarticulate. Mandibular feet in the female 

 armed on the basal joint with a strong bifurcate process, in front of 

 which are three toothed spines ; in the male bearing on the basal 

 joint a large densely setose triangular process, and having the last 

 joint very much elongated ; second pair of jaws having a strong 

 mandibular appendage consisting of two robust tooth-like processes. 

 Eyes of the female small and pale-coloured, of the male large, deep- 

 red, and multilenticular. 



Philomedes (Lilljeborg). 



Shell of moderate strength and density. Superior antennae six- 

 jointed ; in the female short and thick, and bearing several subequal 

 terminal setae of moderate length ; in the male more elongated, two 

 of the terminal setae of excessive length, the antepenultimate joint 

 bearing a stout and densely setose auditory filament. Natatory 

 branch of lower antennae nine-jointed; in the female having the first 

 joint very long, the rest short and subequal ; in the male the first 



