368 



PROCEEDINGS OF THE ACADEMY OF 



[1898. 



DESCRIPTION OF A NEW GENUS AND SPECIES OF MICROTINE RODENT 



FROM SIBERIA. 



BY GERRIT S. MILLER, JR. 



Before the first ocean telegraph cable was laid, the Western 

 Union Telegraph Company organized an expedition to investigate 

 the practicability of an overland international line by way of Alaska 

 and Siberia. A few mammals were collected during this explora- 

 tion, and among them is a mouse representing an uudescribed genus 



and species. It was 

 taken at Plover Bay, 

 Bering Strait, Siberia. 

 In general appearance 

 this animal resembles a 

 lemming. So close is 

 the likeness that the spe- 

 cimen remained for 

 many years in the Na- 

 tional Museum collec- 

 tion labelled ' Myodes.' 

 Recently, however, Mr. 

 F. W. True detected the 

 error in identification 

 and referred the subject 

 to me for further study. 

 I find that the species, 

 while possessing no im- 

 portant characters not 

 found in Microtus and 

 Evotomys, yet combines 



the peculiarities of these 

 Fig. 1. Skull of Aschizomys lemminus (x 2). twQ genera gQ perfectIy 



that it is necessary either to recognize the new form as an annectant 

 genus, or to reduce Evotomys to the rank of a subgenus of Microtus, 

 and treat the Plover Bay animal as still another subgenus. While 

 the latter course would be the more logical, it would involve the 

 serious inconvenience of uniting two large, widely spread, and else- 

 where sharply defined genera. Hence I prefer the first alternative. 



