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Show 292 MR. AV. E. DE WINTON ON CANIS VULPES. [Mar. 7, the animals themselves were by no means new to science. They had been recorded from the Lake by Boehm in 1887. They had also been seen by Air. Aluir, aud obtained by him, and their anatomy described by Air. E. T. Giinther1. But, notAvithstanding this, the Aledusa Avas of perennial interest, in that it is, with the exception of Limnocodium, the single representative of a true freshwater Jellyfish. All the other instances Avhich had been recorded of Jellyfish inhabiting freshwaters had turned out to be examples of the fact that Jellyfish could migrate, under certain circumstances, considerable distances from the sea, just in the same Avay that Crabs and Prawns and flat-fbh were sometimes found far up the estuaries of rivers beyond the tidal range. Nevertheless, all these organisms Avere typically marine, and the very last place where anyone Avould have looked for Jellyfish Avas Lake Tanganyika, on the top of the interior African plateau, and 700 miles from the sea. Mr. Aioore himself had observed the Jellyfish early in Aiarch, and shortly afterwards they began to increase rapidly by budding, so that in a few weeks the bays and open waters of the Lake Avere filled with immense swarms of Medusae. The buds on the manubrium became detached in strings and shreds in such a manner as to curiously resemble minute siphonophores. About June or July the budding ceased, and shortly afterwards ciliated embryos appeared in great quantities, Avhich developed into small Medusae exactly like the buds, and toAvards September all reproductive activity appeared to have come to an end. It thus appeared that the life-cycle of Limnochnida was complete without the introduction of any hydroid stage, and accordingly, although a most careful search had been made among the debris on the bottom of the Lake, upon the shells of molluscs, and upon the appendages of crabs and other Crustacea, no hydroid had ever been found. Hence it was inferred that the various surmises which have been put forward respecting the possibility of Limnochnida being related to the Macro-Medusae Avere probably true. Air. W . E. de AVinton, F.Z.S., exhibited and made remarks upon the tail of a Common Fox (Canisvulpes), showing the gland on the upper surface covered with straight coarse hair, which appeared to be little known. This gland, Avhich emitted an aromatic odour, Avas found in all the Canidae, Avith possibly the exception of Lycaon pictus. Although the bases of the hairs covering the gland were usually almost Avhite, the tips Avere ahvays black ; this colour generally extended to the surrounding hairs, and often formed dark bars on the buttocks. The dark spot on the dorsum of the tail was particularly conspicuous, notably in such Avidely separated species as the AVolves, Azara's Dog, and the Fennec. 1 See Ann. <fe Mag. N. H. ser. 6, xi. p. 269. |