RANGE OF OTTERS 



441 



the claws upon the hind-feet are flattened and somewhat nail- 

 like. There are about ten species, but of course, as is so 

 universally the case, a great many more names have been given. 

 The molar formula is like that of Enliydris save that there is an 

 extra premolar in the upper jaw. There are fourteen pairs of ribs, 

 of which eleven pairs reach the ten-jointed sternum. The caudals 

 are twenty-three. The Cape Otter, the " clawless " Otter, has been 

 separated as a genus Aonyx. So too has the South American 

 Pteronura brasilien&is. But in neither case is the separation allowed 

 by Mr. Thomas in a recent revision of the genus. 1 The latter 

 species has the reputation of being very fierce, and is known in 



FIG. 223. Otter. Lutra vitlyaris. x J. 



Uruguay by the name of " Lobo de pecho bianco." The British 

 species, L. vulyaris, reaches a length of 2 feet or so, with a tail of 

 1 6 inches ; it ranges over the whole of Europe and a large 

 portion of Asia. This Otter often burrows in the banks of the 

 streams which it frequents ; and in the burrow in March or April 

 the female brings forth her young, three to five in number. It 

 will also frequent the sea-coast. 



Fossil Mustelidae. Besides a number of the existing 

 genera there are fossil members of this family which cannot be 

 referred to existing genera. These latter extend back into time 

 as far as the Eocene. Stenoplesictis, one of these Eocene forms 

 referable to the sub-family Mustelinae, is to be distinguished 



1 " Preliminary Notes on the Characters and Synonymy of the different Species 

 of Otter," Proc. Zool. Soc. 1889, p. 190. 



