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Show 104 MR. p. W. BASSETT-SMITII ON [Feb. 3, 4. On new Parasitic Oopepoda from Zanzibar and East Africa, collected by Mr. Cyril Crossland, B.A., B.Sc. By Staff- Surgeon P. W . Bassett-Smith, R.N., F.Z.S. [Received December 4, 1902.] (Text-figures 11 & 12.) Mr. Cyril Crossland, in his recent examination of the marine fauna of Zanzibar and British East Africa, obtained several specimens of parasitic and semiparasitic Copepods, three of which he has been kind enough to allow me to examine. These curiously deformed and often grotesquely-shaped animals are frequently found attached to the gills, &c., or to the surface of fish and other marine animals. A large number from the former which are now described from a variety of different hosts, and from wide geographical areas, I enumerated in Proc. Zool. Soc. 1899, p. 438 ; to this paper I have appended a list of addenda, which I have drawn up with the kind assistance of Mr. E. Bergrotti, of Tammerfers, and others. Not only fish but a number of other marine animals are undoubtedly infested with these parasites, though at present little information concerning them has been collected ; the specimens of Mr. Crossland are therefore particularly interesting. Gerstacker, in Bronn's ‘ Klass. und Ordn. des Thier-Reichs,' 1866-79, Crustacea, vol. v. Copepoda, p. 774, mentions five genera found on Nudibrancli Mollusca: Doridicola Lyd., Eolidicola Sars, belonging to the family Ergasilidae; Artotrogus Boeck, to the family Ascomyzontidae; and Splanchnotropus Hanc. and Ismailia Bergh, to the family Chrondracanthidae. Also nine genera from various Vermes, p. 773. Of the three specimens of Mr. Crossland, two were taken from the kidneys of species of Pleurobrancliids (not determined) and one from the skin of a Sipunculid (A spido siphon). As they were only single specimens it was impossible to dissect them, and therefore the descriptions are necessarily incomplete. The first two evidently belong to the family Chondracanthidae, but do not fall in with the descriptions of any known genus; they appear to be most nearly related to the genus Splanchnotropus of Hancock (Trans. Linn. Soc. vol. xxiv. pp. 51, 55), two species of which he describes, S. gracilis and S. brevipes, taken from Nudi-branclis; the present specimens differ from them, however, in the complete absence of antennae and articulate limbs, and in having the external ovaries elongated and the eggs arranged in single series. 1 have therefore provisionally placed them in a new genus, Chondrocarpus, following closely after Splanchnotropus Hanc. and Diocus Fabr. Chondrocarpus, gen. nov. 2 . Cephalothorax coriaceous, elongated, with four lateral short |