Description of a New Species of Lagomys. 119 



the lower parts are pure white, including the feet and legs, 

 except only the smoky-brown fur on the soles of the hind feet. 

 The fore feet and legs to well above their insertion are included 

 within the pure-white area of the lower surface. The exposed 

 portion of the interior of the ear-conch is covered with a strong 

 growth of coarse hairs. These hairs are pale gray at base, shad- 

 ing into yellowish toward the distal third, and the remainder 

 of tip shiny black. The distribution of the hairs is such that 

 the colors form a distinct yellowish band across the middle of 

 the ear, succeeded by a very distinct black bar that extends 

 along the edge and, at first glance, appears to form a black band 

 bordering the ear. A close examination, however, shows that 

 behind this black bar the actual margin of the ear is very nar- 

 rowly edged with pale grayish-white. The black bar is about 

 3 mm. in width, and is distinct in all the specimens examined. 

 The under fur of the dorsal surface is slaty-black. Above this 

 slaty-black area the longer hairs have a narrow band of pale 

 gray shading into a broader zone of dull yellowish, followed by 

 a distinct black tip. 



The two winter specimens from the Chigmit mountains are 

 without any of the yellowish wash of the skins from the type 

 locality, and the long hairs are mainly pale ashy with faint 

 blackish tips, so that the color is a pale ash-gray. The still paler 

 collar separating the uniform color of head and back is present, 

 as is the dull-gray band across the neck below ; otherwise they 

 are colored similarly to the type specimen. All of the specimens 

 have very long pelage as compared with the southern species, 

 and this is especially noticeable in the three specimens from 

 south of Fort Yukon, on which the long dorsal hairs reach an 

 average length of over 22 mm. 



Measurements. The following average measurements in milli- 

 meters of five dried skins are given merely to serve as an approxi- 

 mation to the true dimensions : Total length, 182 ; hind foot, 

 28.3; ear, 19.1 (measured from anterior base). 



Compared with L. princeps from Idaho and L. schisticeps from 

 the Sierra Nevada of California, the following are the most strik- 

 ing external differences : The hairy, strongly marked ears of the 

 Alaskan animal are conspicuously different from the two south- 

 ern species, both of which latter have the ears thinly covered in 

 front with very short hairs and a much more conspicuous whitish 

 border, On both schisticeps and princeps the yellowish or fulvous 



