ARVICOLA SOCIALIS. ARVICOLA RTJBIDUS. 91 



and Russia, in all grassy districts ; and is found over nearly 

 the whole of Europe, excepting Italy. It is the Mus 

 agrestis of Linnaeus, which he records as a native of Sweden, 

 where it is rather darker in colour, and the tail of a deeper 

 shade above than below (see Ann. Nat. Hist. vol. vii. 1841, 

 p. 270 (Jenyns) ; De Selys, ' Micrommalogie,' p. 104). 



Arvicola socialis. 



Arvicola socialis, Desm, Mamm. Sp. 447. 

 Mus socialis, Pallas. 



Description.- — Tail rather less than one-fourth of the 

 body, whitish, very hairy; ears rather large, as long as 

 the fur, almost naked ; feet white. Fur on the upper 

 parts very soft, even, more than five lines in length, of a 

 pale grey, becoming lighter on the sides, pure white be- 

 neath ; light tawny on the muzzle, which is obtuse ; 

 whiskers white. The head is rather smaller than in A. 

 arvalis. Feeds on roots and bulbs. 



Length of head and body, 3 inches 5 lines ; head, 1 inch 

 1 line ; ears, 4A- lines ; tail, 10| lines. — F. M. 



Inhabits the deserts between the Volga and Jaik near 

 the Caspian Sea. 



Arvicola rubidus. 



Arvicola rubidus, De Selys, Micromm. 

 Arvicola pratensis, Bell, Brit. Quad. 

 Arvicola glareolus, Blasius, Wirbelth. Deutsch. 

 Bank Vole, Bell, I. v. 



Description. — Tail rather more than half the length of 

 the body, covered with short hairs, blackish above, yel- 

 lowish white beneath, concealing the scaly rings, which 

 are about ninety in number; ears rather large, slightly 

 oval, longer than the fur, furnished with small reddish 

 hairs; eyes prominent, but less so than in A. arvalis; 



