_Measurements._--A male from Cottage Lake, King County, measured: total length 287; length of tail 125; hind foot 38. A female from 5 miles southeast of Sequim, Clallam County, measured: 303; 133; 41; ear 27. A male from Quilcene, Jefferson County, measured: 311; 140; 41. _Distribution._--Western Washington west of the Cascade Mountains. The locality records for flying squirrels in the northern Cascade Mountains, given by Taylor and Shaw (1929: 18), when plotted on a distribution map, show overlapping of ranges in this area. The ranges of the three races involved have been drawn on the accompanying map (fig. 92) on the basis of geographic probability and are subject to revision because the specimens from this area have not been examined. Marginal records that may apply to _G. s. oregonensis_ are, from Taylor and Shaw (1929: 18): Nooksack River, Rockport, North Bend and Skamania. _Remarks._--Of all the races occurring in Washington, _oregonensis_ is the most distinct. _Glaucomys s. olympicus_ Elliot must be regarded as a synonym of _oregonensis_. =Glaucomys sabrinus bangsi= (Rhoads) _Sciuropterus alpinus bangsi_ Rhoads, Proc. Acad. Nat. Sci. Philadelphia, p. 321, June, 1897. _Glaucomys sabrinus bangsi_ Howell, N. Amer. Fauna, 44:38, June 13, 1918. _Type._--Obtained in Idaho County, Idaho, by Harbison and Bargamin on March 8, 1897; type in Philadelphia Academy of Natural Sciences. _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. =Glaucomys sabrinus latipes= Howell _Glaucomys sabrinus latipes_ Howell, Proc. Biol. Soc. Washington, 28:112, May 27, 1915. _Type._--Obtained at Glacier, British Columbia, by J. A. Loring, on August 13, 1894; type in United States National Museum.