MURID^ 131 



Sitka spruce belt along the coast of northwestern CaHfornia and 

 southwestern Oresfon. 



Subgenus Lagurus. 

 Pelage long and rather coarse; soles with five tubercles; 

 pattern of third lower molar with two or three closed triangles ; 

 third upper molar with two or three closed triangles and five or 

 six salient angles; palate flattened; audital bullae large and pro- 

 jecting backward. 



Microtus curtatus Cope. (Shortened.) 



SHORT-TAILED MEADOW MOUSE. 



Above pale buffy gray ; soiled white below ; tail pale gray, 

 slightly darker above; very short; skull wide and flat, with short 

 rostrum; audital bullae inflated. 



Length about 140 mm. (5.50 inches); tail vertebrae 27 

 (1.05) ; hind foot 17.5 (.70). 



Type locality, Pigeon Spring, Mount Magruder, Nevada. 



White and Inyo Mountains, California and mountains of 

 western Nevada, principally in sagebrush in dry, barren locali- 

 ties. 



Subgenus Chilotus. 

 Pelage comparatively short and dense ; soles with five tuber- 

 cles; pattern of surface of lower molar without closed triangles; 

 third upper molar with two or three closed triangles and six sal- 

 ient angles; skull low and flat with long slender rostrum. 



Microtus oregoni Bach man. (Of Oregon.) 



OREGON MEADOW MOUSE. 



Above mixed bistre and blackish ; below dusky washed with 

 dull buff; feet dusky; tail blackish, slightly lighter below; ears 

 blackish, longer than the surrounding pelage. 



