320 NORTH AMERICAN FAUNA 61, FISH AND WILDLIFE SERVICE 



suggested that this lemming may have in some degree the tendency 

 that is so strong in Dicrostonyx. 



Clethrionomys rutilus: Red-backed Mouse 

 Clethrionomys rutilus dawsoni 



The wide-ranging red-backed mouse is found practically 

 throughout the whole length of the Alaska Peninsula, for Wet- 

 more obtained a specimen at Frosty Peak, which is not far from 

 the west tip of the peninsula. Furthermore, in 1925, I was in- 

 formed that in the general vicinity of False Pass there was a 

 "red" mouse, whose description accurately fitted that of Clethri- 

 onomys. No evidence of its presence on Unimak Island was 

 obtained. 



Microfus oeconomus: Meadow Mouse 

 Microtus oeconomus kadiacensis 



Osgood (1904, p. 34) discussed the specimens from the base of 

 the Alaska Peninsula, and remarked that — 



All of these seem to be more similar to kadiacensis than to typical operarius, 

 though to a slight extent they partake of the characters of each. From 

 the examination of a very large series of both it appears that in color 

 operarius and kadiacensis are absolutely alike, and that in cranial characters 

 they are very closely related. 



After careful and painstaking study of this material, it seems 

 best to assign M. o. kadiacensis to Kodiak Island exclusively. It 

 is indeed only slightly differentiated, but it may be recognized. 

 It is possible that age has something to do with the character of 

 the skulls from Kodiak, but they appear less robust than those 

 of M. oeconomus opera?~ius. The nasals are slightly different in 

 shape, and the incisive foramen in skulls of kadiacensis tend to be 

 a little shorter and wider. 



Microtus oeconomus operarius 



Aleut (dialect?) : Asookitah (Wetmore) 



Meadow mice inhabiting the Bering Sea coast, including Bristol 

 Bay, the Alaska Peninsula, and Unimak Island, appear to be re- 

 ferable to operarius. Those found on Unimak Island do not ap- 

 pear to be quite typical, but the differences are so slight (if 

 they really exist in comparable specimens) that there seems to be 

 no sound basis for separating them. 



Four specimens of meadow mice were obtained on Sanak Is- 

 land. Curiously enough, these could hardly be said to differ from 

 the mice on Unimak Island and the Peninsula, though they are 



