1903.] Allen, Mammals from Northern British Columbia. 549 



River, taken the last of November. It is the grayest speci- 

 men of the whole series; but several October specimens from 

 Telegraph Creek very closely resemble it. My M. cautus (see 

 this Bulletin, Vol. XII, 1899, p. 7) is a May specimen, also 

 from Liard River, and though more yellowish brown on the 

 back, is easily matched by the brighter specimens of the 

 October series, and is, as stated by' Mr. Bailey T (N. Am. 

 Fauna, No. 17, 1900, p. 48, footnote), a phase of vellerosus. 



The present large series shows that vellerosus is rather 

 darker colored and more rufescent than mordax, and somewhat 

 smaller, the hind foot averaging 21 mm., instead of 22, and 

 the ear 14 instead of 15. Six specimens of mordax (the type 

 and 5 topotypes) measure (cf. Merriam, N. Am. Fauna, No. 5, 

 1891, p. 62) as follows: Total length, 184 (180-200); tail 

 vertebrae, 67.3 (63-77); hind foot, 22 (21-23). Seven adults 

 from Amador County, California, collected and measured by 

 Mr. W. W. Price, range as follows: Total length, 193 (181- 

 202); tail vertebrae, 66.2 (57-67); hind foot, 22.9 (20-25); 

 ear, 15.1 (14-16). Microtus vellerosus seems well-entitled to 

 stand as a northern subspecies of M. mordax. 



20. Microtus drummondi (Aud. & Bach.). DRUMMOND 



VOLE. 



Arvicola drummondi AUD. & BACH., Quad. N. Am., Ill, 1853, 106, 

 pi. cxxxv. ^ " Valley of the Rocky Mountains." 



Microtus drummondi BAILEY, N. Am. Fauna, No. 17, June, 1900, 

 22. " Type locality, Rocky Mountains, vicinity of Jasper House, 

 Alberta." 



Represented by 39 specimens, taken as follows: Cheonnee 

 Mountains, 3 specimens, July 22-25; Telegraph Creek, i, 

 July 27 ; Shesley River, 4, August 25 to September i ; Tahltan 

 River, i, August 18; Level Mountain, 30, September 1021. 

 Only 1 2 are fully adult, 7 of which are males and 5 are females ; 

 all of the adults, except one, are from Level Mountain, and 



1 In his comment on these species he has transposed the names vellerosus and cautus; 

 his remarks respecting the former relate to the latter, and vice versa. 



