_Measurements._--Twenty males and 15 females from western Washington average, respectively: total length 230, 233; length of tail 140, 140; hind foot 33, 32.8; ear 14.9, 16.3; weight 23.7, 25.7 grams. _Distribution._--Western Washington and the Cascade Mountains, east in the northern Cascades at least to Tomyhoi Lake (W.W.D.). _Remarks._--Actual intergrades between _trinotatus_ and _kootenayensis_ have not been examined but the differences separating the two forms are of the degree that usually distinguish subspecies. Since _trinotatus_ occurs in the high Cascades as far east as Mount Baker, at least, and _kootenayensis_ probably occurs in the northeastern Cascades, the two forms doubtless come together in the rugged, inaccessible area between these two localities. Further collecting will probably show a narrow zone of intergradation in extreme western Okanogan County. [Illustration: FIG. 124. Distribution of the big jumping mouse in Washington. A. _Zapus princeps oregonus._ B. _Zapus princeps idahoensis._ C. _Zapus princeps kootenayensis._ D. _Zapus princeps trinotatus._] =Zapus princeps kootenayensis= Anderson _Zapus princeps kootenayensis_ Anderson, Ann. Rept. Nat. Mus. Canada for 1931, p. 108, November 24. 1932. _Type._--Obtained on Green Mountain, 6,000 ft., 10 miles north of Rossland, West Kootenay District, British Columbia, by R. M. Anderson, on July 18, 1929; type in National Museum of Canada. _Racial characters._--Similar to _oregonus_ but paler; yellow more faded. _Measurements._--Twenty females, including 15 topotypes, average (Anderson, 1932: 109): total length 245; length of tail 140; hind foot 30.5. _Distribution._--Northeastern Washington. Specimens from Sullivan Lake (E.S.B.) have been examined. =Zapus princeps idahoensis= Davis _Zapus princeps idahoensis_ Davis, Jour. Mamm., 15:221, August 10, 1934. _Type._--Obtained 5 miles east of Warm Lake, 7,000 feet elevation, Valley County, Idaho, by W. B. Davis; type in Museum of Vertebrate Zoölogy. _Racial characters._--Similar to _kootenayensis_ but brighter in color, more ochraceous. Similar to _oregonus_ but paler, more yellowish. _Measurements._--Davis (1939:339) gives the measurements of six adult topotypes as: total length 240; length of tail 144; hind foot 31. _Distribution._--A single specimen in the Charles R. Conner Museum from Kamiak Butte, Whitman County, is referable to this race. =Zapus princeps oregonus= Preble _Zapus princeps oregonus_ Preble, N. Amer. Fauna. 15:24, August 8, 1899. _Type._--Obtained at Elgin, Union County, Oregon, by E. A. Preble, on May 29, 1896; type in United States National Museum. _Racial characters._--Small size, pale color.