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Show 122 DR. G. STEWARDSONT BRADY ON [May 17, similar to what one would expect in ordinary Northern collections. With the exception of one species, for which I have thought it best to propose a new generic name-Eclocyclops-all are referable to familiar European genei'a. C yclops l e u c k a r t i Claus. This appears to be less plentiful in the Natal gatherings than any of the following species, though more conspicuous owing to its greater size. The form described by me years ago under the specific name scourfieldi* has been identified by other authors (Lilljeborg, Herrick, Schmeil) with C. leuckarti Claus. I am doubtful as to the correctness of this identification. Both Schmeil f and Herrick t figure, with differences, peculiar pellucid marginal laminae on the last two joints of the larger antennae. I have been unable to detect any such structure in my British specimens of C. scourfieldi, neither does it exist in the Natal specimens nor in others from Ceylon which I refer to the same species. And it may be noted that Lilljeborg, while accepting SchmeiTs description and figures as belonging to C. leuckarti, does not himself refer in his definition to these antennal laminae. Herrick, on the other hand, figures and describes them, and expresses a doubt as to the identity of the species with C. scourfieldi. I do not myself possess authentic specimens of C. leuckarti, and must be content for the present to leave the question in suspense. C yclops p u s il lu s , n. sp. (Plate YI. figs. 11-18.) Female. Body slender, tapering gradually from before backwards (fig. 11); thoracic segments not produced at the angles, except the last which is extremely short and angulated : abdomen very slender, the first segment nearly as long as the united lengths of the following three segments; furcal segments slender, scarcely longer than the preceding abdominal segment; principal tail-seta nearly as long as the whole abdomen. Ovisacs closely adpressed to the abdomen and containing only a few comparatively large eggs. Antennules twelve-jointed, slender, somewhat longer than the entire cephalothorax, bearing numerous long setae (fig. 12). All the branches of the first four pairs of feet three-jointed ; spines of the first pair (fig. 17) very slender and setiform ; fifth pair (fig. 18) rudimentary, almost obsolete, consisting of a minute papilla from which arise two unequal setae. Length, exclusive of tail-setae, 046 mm. This is the smallest species of Cyclops with which I am acquainted. But its general development and the fact of many specimens bearing ova, indicate that it is not an immature form. * Brady, G. S. " A Revision of the British Species of Freshwater Cyclopida; and Calanidse" (Nat. Hist. Trans. Northumberland & Durham, vol. xi., 1891). f Schmeil, Deutschlands freilebende Susswasser-Copepoden. 1 Teil Cvclopidae 1892. X Herrick, Synopsis of the Entomostraca of Minnesota, 1895. |