442 BEARS CHAP. 



from living Mustelines hy its comparatively long legs. In this 

 genus as in several others there are two upper molars. 



Fam. 8. Ursidae. — This family is nearly universal in dis- 

 tribution, and consists of but three genera, Ursi's, Mclursus, and 

 Aeluro2){'s. 



ITrsus has the palms and soles naked except in the Tolar 

 Bear, which needs a furry sole to walk witli ease upon ice 

 surfaces. The ears are fairly large, and the nose may or may 

 not be traversed by a median groove.^ The molar formula - is 

 Pm |- M -|. The brain is naturally (liecause of the size of the 

 animals of this genus) richly convoluted. The lobate kidneys 

 have already been mentioned in defining this family (see p. 426). 



A very large number of species of Bears have been described. 



-^::' 



Ftg. •2-24. — Iliiiialay.an Bear. UrsKS tihetanvs. x j\. 



But it is the opinion of Mr. Lydekker ^ and of others that many 

 of these are really to be referred to the European Brown Bear ; 

 in this event the Grizzly of North America, the Tsabelline Bear, 

 the Syrian Bear, a Bear from Algeria, the Kamschatkan and 

 Japanese Bears, besides the extinct Irrsus fossilis of Pleistocene 

 caves, are to be regarded as slight modifications of ITrsus 

 arctos. On the other hand, the great Cave Beav/U. sjyelaeus, 



^ Even a]i]iareiitly in the same species. 



.- The number oF premolars is reduced in the Polar Bear. 



3 '^The Blue Bear of Thibet," eto., Proc. Zool Soc. 1897, p. 412. 



