Racial characters.—Similar to oregonensis but larger and paler throughout.
Measurements.—A female from Wildcat Spring, Columbia County, measured: total length 333; length of tail 147; hind foot 45; ear 29; weight 151 grams.
Distribution.—Found only in the Blue Mountains of extreme southeastern Washington.
Glaucomys sabrinus columbiensis [Howell]
Glaucomys sabrinus columbiensis [Howell], Proc. Biol. Soc. Washington, 28:111, May 27, 1915.
Type.—Obtained at Okanogan, British Columbia, by Allan Brooks on May 9, 1898; type in United States National Museum.
Racial characters.—Larger than oregonensis and paler. Similar to bangsi but paler, especially beneath, and less reddish above.
Measurements.—[Howell] (1918: 46) gives the average of two subadult topotypes as: total length 313; length of tail 143; hind foot 42.
Distribution.—Northeastern Washington, probably extending, from records of [Taylor] and [Shaw] (1929: 18), west to Mazama and Stehekin and east to Molson.