_Specimens examined._--Total 214, as follows: _Yukon Territory_: 2 mi. W Teslin River, 2400 ft., 16 mi. S and 56 mi. E Whitehorse, 8; W side Teslin River, 2300 ft., 16 mi. S and 58 mi. E Whitehorse, 24; E side Teslin River, 2300 ft., 16 mi. S and 59 mi. E Whitehorse, 7. _British Columbia_: 1 mi. NW jct. Irons Creek and Liard River, 10; Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 6; N side Liard River, ½ mi. W jct. Trout River and Liard River, 13; ¼ mi. S jct. Trout River and Liard River, 20; SE end Muncho Lake, 5; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 45; N side Muskwa River, 1200 ft., 4 mi. W Fort Nelson, 9; North Fork Tetsa River, 3900 ft., 4 mi. ENE Summit Pass, 13; Summit Pass, 4200 ft., 10 mi. S and 70 mi. W Fort Nelson, 17; E side Minaker River, 1 mi. W Trutch, 18; Beatton River, 115 mi. S Fort Nelson, 2; 5 mi. W and 3 mi. N Fort St. John, 7. _Alberta_: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 10. _Remarks._--Specimens from 2 miles west of Teslin River resemble _P. m. borealis_ more than _P. m. algidus_ both in size of skull and in color, although I find it difficult to distinguish the specimens by color. Alcorn, like Rand (1945:43), found the mouse in almost every habitat along the Alaska Highway. On the east side of the Minaker River, one mile west of Trutch, Alcorn took 26 _Peromyscus_ and four _Microtus_ in 70 museum special traps baited with chewed rolled oats, set in a grassy area where there were birches and clumps of willows. _Peromyscus_ was usually abundant in old construction camps along the highway; on July 27 in 50 traps set under abandoned buildings at Summit Pass, Alcorn took 21 _Peromyscus_. Apparently, as Swarth (1936:402) notes, the white-footed mouse makes itself at home in such buildings, and local populations probably increase as a result of the artificial environment that provides favorable conditions for existence. Neotoma cinerea drummondii (Richardson) Bushy-tailed Wood Rat _Myoxus drummondii_ Richardson, Zool. Jour., 3:517, 1828. (Type probably from near Jasper House, Alberta, Canada.) _Neotoma cinerea drummondii_ Merriam, Proc. Biol. Soc. Washington, 7:25, April 13, 1892. _Specimens examined._--Total 4, as follows: _British Columbia_: Summit Pass, 4500 ft., 10 mi. S and 70 mi. W of Fort Nelson, 1; 5 mi. W and 3 mi. N Fort St. John, 3. _Remarks._--Wood rats were obtained at only two locations, Alcorn's field notes indicating that the animals were rare and spotty in distribution. Rand (1944:44) comments that the rats were "scarce north of the Lower Liard Crossing."