1916] Kellogg: Mammals and Birds of Northern California 363 



and the arched dorsal line of the skull in contrast to the conditions 

 in E. mazama, which species is described (Bailey, 1897, p. 132) as 

 being bright-colored and with a notably flat-topped skull. Our 

 specimens agree with dbscurus also in the basilar length of the 

 skull and in the zygomatic and mastoid breadth. In external 

 measurements our examples do not agree with obscurus so well, 

 at least with the published measurements of the type of E. obscurus; 

 but in a species of which so few individuals have been taken some 

 latitude may be allowed in this respect. Our specimens measure as 

 follows: no. 13392,5 adult, total length, 147 millimeters; tail verte- 

 brae, 43; hind foot, 20. No. 13391, <J , total length, 137; tail verte- 

 brae, 40; hind foot, 19.5. The type specimen of obscurus measured 

 (Merriam, 1897a, p. 72) total length, 155 millimeters; tail vertebrae, 

 47 ; hind foot, 17. Thus we see that our two specimens average 

 smaller in total length and that of tail vertebrae, but have a longer 

 hind foot. In this latter respect they incline toward E. mazama, 

 in four specimens of which according to Merriam (1897a, p. 72) 

 the hind foot measured 18.75 millimeters. 



Both of our specimens were taken in dark shady places among 

 the pines, in traps baited with oatmeal. 



Microtus montanus montanus (Peale) 



Peale Meadow Mouse 



One specimen (no. 13404), from Mayten, Siskiyou County. 



Microtus calif ornicus calif ornicus (Peale) 

 California Meadow Mouse 

 This meadow mouse was only taken at our two lowest summer 

 camps, Scott River and Mayten, and in winter at Helena and Tower 

 House. It was not at all commou at Scott River, which was rather 

 a wet place, but the dry grass in the other localities was, as usual, 

 full of their runways. Thirty-three specimens were secured: nos. 

 13393-13404, 13405-13407, 12793-12811. from Helena, Tower House, 

 Mayten and Scott River. The Helena series is perceptibly darker 

 in tone of coloration than the specimens from elsewhere. 



Microtus mordax mordax (Merriam) 

 Cantankerous Meadow Mouse 

 A series of seventy-one specimens (nos. 13408-13476) of this 



