146 MAMMALIA. 



Buff. XIII, xiv. (The Common Hamster.) Larger than the 

 Rat ; of a reddish-grey above, black on the flanks and under- 

 neath, with three whitish spots on each side. The feet, a 

 spot under the throat, and another under the breast white ; 

 some individuals are all black. This animal, so agreeably varied 

 in colour, is one of the most noxious that exist, gathering large 

 quantities of grain with which it fills its burrow that is some- 

 times seven feet deep. It is common in all the sandy regions, 

 that extend from the north of Germany to Siberia. 



This last country produces several small species of Hamsters 

 described by Pallas.(l) 



Arvicola, Lacep. 



The Arvicolse, like the Rats, have three grinders every where, but 

 without roots, each one being formed of triangular prisms, placed 

 on two alternate lines. They may be subdivided into several 

 groups, viz. 



Fiber, Cuv. 



The Ondatras or Field Rats having semi-palmated hind feet, a long, 

 scaly and compressed tail, of which one species only is well known. 

 F. vulgaris; Castor zibeticus, L.; Mus zihetkus, Gm. ; Buff. X, 

 i. (The Canadian Musk-Rat or Ondatra.) As large as a Rab- 

 bit, of a reddish-grey. In winter they construct, on the ice, a 

 hut of earth, in which several of them reside together, passing 

 through a hole in the bottom, for the roots of the acorus on 

 which they feed. They neither dive nor swim well. It is this 

 habit of building which has induced some authors to refer the 

 Ondatra to the genus Castor. The second subdivision is 

 that of 



Arvicola, Cuv. Hypud^eus, Illig. 



Our common Field Rats, which have a hairy tail, about the length 

 of the body, and simple or not palmated feet. 



Jl. vulgaris ', Mus amphibius, L. ; Buff. VII, xliii. (The Water 

 Rat.) A little larger than the Common Rat, of a deep greyish- 

 brown 5 tail the length of the body. Inhabits the banks of rivers, 

 8cc. and burrows in marshy places. 



t/3. terrestris ; Mus terrestris, Lin. (The Schermaus.) Seems 

 to differ from the Water Rat only in being somewhat smaller; 

 its tail also is shorter. It lives under ground like the Mole, 



(1) M. accedula. M. arenarius.M. phoeus. M. songarus. M. furunculus. 

 See Pall. Glir. and Sch. 



