298 MONOGRAPHS OF NORTH AMERICAN RODEDTIA. 



the specimens, while there is generally a well-marked brownish area on the mid- 

 dle oi the back, which varies in tint from pale yellowish-brown to dark reddish- 

 brown and even reddish-fuscous. Generally, 1 lie upper surface of the head and 



the anterior surface of the ears are but little lighter-colored than in summer; 

 but there is in some a broad baud running from the base of the ears to the 

 nose, on each side of the head, more or less nearly pure white, and occasion- 

 all}- the whole upper surface of the head is yellowish-white. From the dates 

 on the labels, this species appears to assume its winter dress in November, 

 as I have observed it to do in Southwestern Wyoming; but in Northwestern 

 Kansas I found that a considerable proportion of the individuals observed 

 retained nearly their summer colors in midwinter; they then have a much 

 fuller, softer coat than in summer, and the general color of the upper surface, 

 the sides of the body, and the limbs is much more strongly suffused with 

 fulvous than in summer specimens. The under fur is also very thick and 

 silky, and pure white, instead of being more or less plumbeous, as in summer. 

 In the specimens from more northern localities, every degree of whiteness is 

 presented, from those that are scarcely lighter than in summer to those which 

 have a uniformly nearly pure white surface. 



In summer, the color of the dorsal surface varies considerably in respect 

 to the intensity of the yellowish suffusion; in some, it is so faint as to be 

 scarcely appreciable, while in others it presents a pale golden hue. In several 

 specimens from Ogden, Utah, and in one from Fort Crook, California, this 

 suffusion partakes of a faint reddish tint, and there is a more decided grayish 

 line on the upper surface of the tail than in those from the plains east of the 

 Rocky Mountains. 



Several very young specimens from the valley of the Yellowstone do not 

 differ essentially in color from the adult. 



This species was first described by Lewis and Clarke, in 1814, in the 

 history of their expedition across the continent (vol. ii, p. 178), but they 

 omitted to give it a distinctive name. Harlan, in 1825, copied their descrip- 

 tion, indicating the species, however, merely as " Lepus Virginian us, var. ?"; 

 thus partially confounding it with his Lepus virgwianus (=z L. americanus 

 auct.), or the White Hare of the Eastern States. Dr. Richardson, while 

 recognizing it as distinct from the L. americanus, identified it with Harlan's 

 Lepus virginianus, he not only redescribing it from a "mutilated winter skin'', 

 but also quoting Lewis and Clarke's description. In 1837, Dr. Bachman 



