ARCTOMYS. MARMOT. 



Generic Character. 



Denies Primores cuneati, duo 

 in utraque maxilla. 



Molares superiores utrinque 

 quinque, inferiores qua- 

 tuor. 



Clavicula perfectae. 



Front- teeth two in each jaw, 

 strong, sharp, and cuneat- 

 ed. 



Grinders in the upper jaw 

 five on each side, in the 

 lower jaw four. 



Clavicles or collar-bones in 

 the skeleton. 



The genus Arctomys or Marmot differs from 

 that of Mus in so few particulars as to make it 

 somewhat doubtful whether it ought to be kept 

 separate or not. These animals are of a thick 

 form, with large, roundish^ and somewhat flat- 

 tened heads, small mouths^, the fissure having a 

 somewhat perpendicular appearance; ears very 

 short, and sometimes none ; a short villous tail ; 

 tetradactyle fore-feet with a very small thumb, 

 and pentadactyle hind-feet: the skeleton is fur- 

 nished with clavicles or collar-bones; and the 

 caecum or appendicular intestine is very large. 

 They are diurnal animals ; feed on roots, grain, 

 &c. which they often collect into heaps. They re- 

 side in subterraneous holes or burrows, and sleep 

 during the winter. 



