Synaptomys (Mictomys) dalli Merriam, Proc. Biol. Soc. Washington, 10:62, March 19, 1896. (Type from Nulato, Alaska.)
Synaptomys borealis dalli A. B. Howell, N. Amer. Fauna, 50:24, (June 30) August 5, 1927.
Specimens examined.—Total 6, as follows: Alaska: E side Deadman Lake, 1800 ft., 15 mi. SE Northway, 1. Yukon Territory: McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 5.
Remarks.—The northern bog lemming is evidently not generally distributed along the Alaska Highway but may be locally numerous in cover of grass and sedge especially in marsh and bog habitat. Five specimens were obtained in a grassy area 30 feet wide by 60 feet long which was approximately 50 feet from McIntyre Creek in the Yukon Territory. In 22 mouse traps set the first night in this locality, three Synaptomys, six Microtus and one Sorex were taken. One additional Synaptomys was taken on each of the following two nights in the same area. At Deadman Lake, Alaska, one Synaptomys was taken in heavy sedge bordering a small pond.
Clethrionomys rutilus dawsoni (Merriam)
Dawson Red-backed Mouse
Evotomys dawsoni Merriam, Amer. Nat., 22:650, July, 1888. (Type from Finlayson River, a northern source of the Liard River, lat. 61° 30' N, long. 129° 30' W, Yukon, Canada.)
Clethrionomys rutilus dawsoni Rausch, Jour. Washington Acad. Sci., 40:135, April 21, 1950.
Specimens examined.—Total 126, as follows: Alaska: Chatanika River, 700 ft., 14 mi. E and 25 mi. N Fairbanks, 17; 1 mi. SW Fairbanks, 440 ft., 1; N side Salcha River, 600 ft., 25 mi. S and 20 mi. E Fairbanks, 15; 25 mi. S and 20 mi. E Fairbanks, 3; Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction, 32; Tok Junction, 1600 ft., 1; E side Deadman Lake, 1800 ft., 15 mi. SE Northway, 9; 1 mi. NE Anchorage, 100 ft., 9; Glenn Highway, 6 mi. WSW Snowshoe Lake, 1; E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 2; 1 mi. S Haines, 5 ft., 2. Yukon [Territory]: Jct. Grafe Creek and Edith Creek, 2; 6 mi. SW Kluane, 2250 ft., 4; 2 mi. NNW Whitehorse, 2100 ft., 2; W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 6; SW end Desadeash Lake, 15. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 1; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 2; Summit Pass, 4500 ft., 10 mi. S and 70 mi. W Fort Nelson, 2.
Remarks.—Specimens from one mile northeast of Anchorage show little tendency toward C. r. orca from the Prince William Sound area (see Orr, 1945:73). One specimen from this locality is slightly darker than the others.