RODENTIA. MURIDiE. 59 



mer, but the fur remains on the margins, of a mixed white and 

 blackish-brown, the latter prevailing at the tips ; the tail is white 

 beneath ; on its upper surface, the gray and brown colors appear 

 through the white ; mystachial bristles as in winter. 



Dimensions. 



ft. in. t'tbs. 



Length of the head and body, 17 



" from the nose to the middle claw, . . . 2 3 5 



" of the head, 4 3 



" from the nose to the insertion of the ear, . . 3 5 



" " " ears posteriorly, . . . 3 5 



" of the three inside nails of the hind feet, . . 5 



Tail, 015 



Skull. 



From the insertion of the incisors to the occipital spine, . 4 6| 



" " " " foramen magnum, 2 6£ 



" " " " meatus extern us, 2 9 



Width, 17 



Height, 14 



Observations. Godman, in his " Natural History," gives the 

 length of this animal as 14 inches, while Richardson, in his 

 " Northern Zoology," gives it as 19 inches. The specimen 

 before me is 16 inches. There is, therefore, some variation, 

 probably, in full grown individuals, which depends on climate, 

 food, &c. The skull of my specimen is longer and larger than 

 the one measured by Richardson. This species is common 

 throughout the New England States, and is known generally as 

 the White Rabbit. It is found, however, far to the north, as at 

 Fort Enterprise on McKenzie's River, in latitude 6S°. As food, 

 it is usually esteemed. It is taken in snares and traps set in its 

 paths, into which it is often driven by hounds. The fur is not 

 much esteemed. The limbs of Rabbits and Hares are so con- 

 structed, that their movements are almost necessarily in leaps or 

 bounds. 



FAMILY X. MURIDJE. The Rat Family. 

 Genus Arvicola. Desm. Mus. Lin. 



— . 



— > 



Generic characters. Dental system ; incisors ■§ ; canines £ 

 molars |=f ; = 16 ; deeply grooved externally. Muzzle obtuse ; 

 tail round Vmd hairy, shorter than the body. 



