The animals available from Glacier, British Columbia, are in color more nearly like _Z. p. saltator_ and cranially combine the characters of _Z. p. idahoensis_, _Z. p. saltator_, and _Z. p. kootenayensis_. The sum total of their characters places them with _Z. p. saltator_. Anderson (1932:108) remarks on the disparity of size between the two sexes of _Z. p. kootenayensis_, stating that females are considerably larger than males. I have examined most of the material used in the original description and find that animals of like age in the two sexes show no significant size difference. Anderson (_loc. cit._) seems to have compared young males with adult females. _Specimens examined._--Total, 68, distributed as follows: BRITISH COLUMBIA: Manning Park, 3 (PM); _Good Fellow Creek, Manning Park_, 1 (PM); _Mt. Beaver Valley, 6300 ft., Manning Park_, 1 (PM); _Timberline Valley, 6500 ft._, 3 (PM); _Allison Pass, 1 mi. E Manning Park_, 1 (PM); Monashee Pass, 4000 ft., 13 (PM); Hope-Princeton Summit, 5500 ft., 1 (NMC); _Hedley, Stirling Creek_, 1 (NMC); Anarchist Mts., 1 (PM); Fairview-Keremeos Summit, 5 (NMC); _Westbridge_, 2 (NMC); _Midway_, 2 (NMC); Green Mtn., near Rossland, 6000 ft., 12 (11 NMC, 1 MVZ); _Mt. Old Glory, 7000 ft., Rossland_, 5 (4 NMC, 1 MVZ); _Rossland, 5800 ft._, 12 (11 NMC, 1 MVZ); Camp 6, Meadow Creek, 7 mi. SE of Yahk, 1 (NMC). IDAHO: _Bonner County_: 5 mi. W Cocolalla, 3500 ft., 2 (MVZ). _Boundary County_: 4 mi. W Meadow Creek, 3000 ft., 2 (MVZ). _Marginal records._--British Columbia: Monashee Pass, 4000 ft.; Camp 6, Meadow Creek, 7 mi. SE Yahk. Idaho: 4 mi. W Meadow Creek, 3000 ft.; 5 mi. W Cocolalla, 3500 ft. British Columbia: Hope-Princeton Summit, 5500 ft.; Manning Park. =Zapus princeps luteus= Miller _Zapus luteus_, Miller, Proc. Biol. Soc. Washington, 24:253, December 23, 1911. _Zapus luteus australis_, Bailey, Proc. Biol. Soc. Washington, 26:132, May 21, 1913. Type from Socorro, Socorro County, New Mexico. _Type._--Female, adult, skin and skull, No. 133601, U. S. Nat. Mus. Biol. Surv. Coll., Espanola, 5000 ft., Rio Arriba Co., New Mexico; obtained on June 24, 1904, by McClure Surber, original No. 162. _Range._--White Mt's of southern Apache County and northern Greenlee County, Arizona; in New Mexico, from the Sacramento Mt's, Otero County, northward to the San Juan Mt's, Rio Arriba County. See fig. 46. Zonal range: Lower Sonoran (1 individual), Upper Sonoran, Transition, and Canadian.