202 CAENIVOEA. 



malar process being developed. In this character it is distinguished both from Aonyx 

 and Lutra^ but its dentition is essentially that of Lutra. Dr. Gray referred Hydrogale 

 to that division of the Lutrina which he considered to be distinguished by the under 

 surface of the feet being sprinkled with scattered, soft hairs, but the artificial 

 nature of this character is evident by the fact that in the supposed naked-palmed 

 and nude-soled section, a semi-adult Otter (No. 45, 1, 8, 367) referred by Dr. Gray to 

 L, monticola, Hodgson, has its palms and soles sprinkled with hairs as in Hydrogale ; 

 and this is also the case in a small-clawed Otter from Madras (No. 67, 11, 14, 2). 

 It would seem, therefore, that the characters which Dr. Gray selected to separate 

 Hydrogale do not belong exclusively to it, but occur also in the genus Lutra. 



Temminck^ considered the Otter of Japan as identical with the European species, 

 but Dr. Gray went so far in the opposite direction as to regard it as a distinct 

 genus, which he called Lutronectes? The two skulls on which this genus has been 

 founded are in the Eritish Museum. They are both young skulls, but the orbital 

 processes, for their age, are not less developed than in examples of Lutra vulgaris 

 of corresponding age, and I cannot see that the flesh-tooth differs in any essential 

 particular from the flesh-tooth of Lutra. The arrangement of the intermaxillaries 

 and the character of the nasals are the same as in the common Otter ; — in short, 

 these skuUs do not yield any characters by which they can be separated generically 

 from Lutra. 



The distinctive features of the genus Aonyx which would appear to give it 

 sub- generic rank are the shorter and more globose cranium as compared ^\\h Lutra; 

 the relatively greater size of the molars ;^ and the inner portion of the last molar 

 being the largest part of the tooth, while in Lutra the outer exceeds the inner half ; 

 the almost general absence of the first upper premolar ; and the rudimentary claws 

 which are associated with much more feebly developed finger and toe bones, which 

 are much tapered to a point, while in Lutra these bones are strong and well 

 developed. The skeleton generally of the Asiatic species is also of a much lighter 

 build than in Lutra. The modification of its extremities as it penetrates to the 

 skeleton is quite as important a character generically considered as the remarkable 

 flattening of the phalanges of the hind feet of Enhydris lutris. Unfortunately 

 we do not possess any information regarding the special habits of Aonyx as con- 

 trasted with those of the longer-clawed Otters. The genus Aonyx, ^ as is well 

 known, was founded by Lesson' for the reception of the large African Otter, Lutra 

 munguis, E. Cuv., which greatly exceeds in size any example of Lutra {Aonyx) 

 leptonyx. 



Dr. Gray^ was of the opinion that there were two distinct Otters in Eormosa, 

 one which he referred to L. chinensis, and another, of which he obtained only the front 

 part of the upper jaw, with the teeth in change from the milk to the permanent series. 



1 Fauna Japonica, Mamm. 1847, p. 35. '^ Also Anahyster, Murray, Proc. Eoyal Phys. 

 ^ Proc. Zool Soc. 1867, p. 180, woodcut. Soc. Edin. 1860, p. 157. 



2 Giebel Odontog. 1855, pi. xii, fig. 10, milk-teeth. s ^^^^ ^^ Mamm. 1827, p. 157. 



Zeits. Ges. Naturwissen., 1868, vol. xxxi. p. 217. ^ Proc, Zool, Soc. 1867, p. 182. 



