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Show 1871.] MR. G. S. BRADY ON EUROPEAN CYPRIDINI D.E. 291 laminae being the same in both sexes. The structure is, in fact, entirely that of a female Bradycinetus. Further, on examining a specimen 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. grcenlandica" they number about thirty as in B. brenda. Adopting these views, the genera of European Cypridinidae 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 subconical 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 |