OCR Text |
Show 1889.] DIFFERENT SPECIES OF OTTER. 191 Dr. A. Nehring, of Berlin, Dr. von Lorenz, of Vienna, and Mr. J. W . Clark, of Cambridge, for assistance either by letter or by loan of specimens. This assistance has in many cases been of most material aid in making out the synonymy of the obscurer forms. Firstly, as to the genera which should be admitted within the subfamily Lutrinae. Putting aside Enhydris as unquestionably good, and Barangia, Lontra, Nutria, Hydrogale, Latax, and Lutro-nectes of Gray *•*, and Leptonyx of Lesson, as unquestionably bad, we have only to consider Aonyx, Lesson2 (syn. Anahyster, Murray 3 ), and Pteronura, Gray 4 (syn. Saricovia, Lesson5). The first of these, Aonyx, was founded on the Cape Clawless Otter; its generic characters depending on the lesser development of the webbing between the toes and on the reduction of the claws. The latter character also occurs, in a rather less degree, in the Indian Clawless Otter, which nevertheless, as Mr. Blanford has shown8, presents no special genetic affinity with the African form, a fact that quite disproves its generic value in the group. The skull and dentition of Aonyx are wholly those of a true Lutra, and therefore I think it must be certainly amalgamated with that genus, of the members of which L. bar ang is apparently most closely allied to it. The characters of Pteronura, again, appear to be clearly of specific and not of generic importance. The corded margin to the tail is only an exaggeration, suitable to so large a species, of the flattened stale of that organ in other Otters; while in the remarkable narrowness of its frontal region, certainly the most peculiar character of its skull, this species does not differ from such narrow-fronted Otters as L. sumatrana or L. maculicollis to a greater extent than the latter do from the broad-fronted L. capensis, L. felina, and L. paranensis. The whole of the living species of Otters, excepting of course the Sea-Otter, appear therefore to be most correctly placed in one single genus only. This genus, Lutra, has the widest distribution known among the non-volant Mammalia, its range extending over the whole globe with the exceptions of the Australasian Region, of Madagascar, and of the extreme Arctic and Antarctic poles. Pending the impossibility of drawing up a natural arrangement, the species may best be treated geographically. ORIENTAL OTTERS. The synonymy of the Oriental Otters is exceedingly confused, chiefly owing to Sir Stamford Raffles, in his account of the Mammals of Sumatra, having given native names, without descriptions, to the two species he found there, which names were afterwards differently applied by different authors to the three species actually occurring in that island. 1 P. Z. S. 1865, pp. 123-133. 2 Man. Mamm. p. 157 (1827). 3 P. R. Phys. Soc. Edinb. ii. p. 158 (1860). 4 Charlesw. Mag. N. H. i. p. 580 (1837). 5 N. Tabl. R. A., Mamm. p. 72 (1842). B Mamm. Brit. Ind. p. 188 (1888). |