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, Lesson" (syn. Anahyster, Murray '), 

 and Pteronura, Gray * (syn. Saricovia, Lesson ^). 



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 Lidian 

 Clawless Otter, which nevertheless, as Mr. Blanford has shown % 

 presents no special genetic affinity with the African form, a fact that 

 quite disproves its generic value in the group. The skull and den- 

 tition oi Aonyx are wholly those of a true Lw^ra, and therefore I 

 think it must be certainly amalgamated with that genus, of the 

 members of which Z. barang is apparently most closely aUied to it. 



The characters of Pteronura, again, appear to be clearly of spe- 

 cific 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 i. 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 ot 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 diflferent 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). 

 * Charlesw. Mag. N. H. i. p. 580 (1837). 



5 N. Tabl. E. A., Mamm. p. 72 (1842). 

 " Mamm. Brit Ind. p. 188 (1888). 



