_Peromyscus akeleyi_ Elliot, Field Columb. Mus. Publ. 30., zoöl. ser., 1:226. February 1, 1899 (type from Elwha River, Olympic Mountains, Washington). _Peromyscus maniculatus oreas_ Osgood, N. Amer. Fauna, 28:51, April 17, 1909. _Type._--Obtained on Church Mountain, 6,500 ft., Mt. Baker Range, near the U. S. boundary, British Columbia, by Allan Brooks on August 29, 1896; type in Museum of Comparative Zoölogy. _Racial characters._--Size large; tail more than 50 per cent of total length; color of upper parts reddish. _Measurements._--Twenty-five males and 15 females average: total length 202; length of tail 110; hind foot 22.6; ear 18.7. _Distribution._--From the Cascade Mountains west to the Pacific Ocean, save for the Puget Sound area and a narrow band extending southward nearly to the Columbia River. Marginal localities along the west side of Puget Sound are: Deer Park (W.W.D.), Lake Cushman (W.W.D.), and Kelso (M.V.Z.). Marginal localities on the west side of the Cascade Mountains are: Tomyhoi Lake (W.W.D.), Forks of Skykomish River (W.W.D.), North Bend (W.W.D.), Mt. St. Helens (V.B.S.) and Yacolt (M.V.Z.). Marginal localities on the east slope of the Cascade Mountains are: Grouse Creek (W.W.D.), Lake Wenatchee (W.W.D.), Easton (W.W.D.), Morrison Springs Ranger Station (W.W.D.) and Wind River C.C.C. Camp (W.W.D.). =Peromyscus maniculatus hollisteri= Osgood Peromyscus maniculatus hollisteri Osgood, N. Amer. Fauna, 28:62, April 17, 1909. _Type._--Obtained at Friday Harbor, San Juan Island, San Juan County, Washington, by N. Hollister on October 23, 1903; type in United States National Museum. _Racial characters._--Similar to _oreas_ but darker, less reddish, and with much shorter tail. Length of tail about 40 per cent of total length. _Measurements._--Populations of deer mice on the various islands vary slightly in average measurements. The average measurements of 10 males and 10 females from San Juan Island, 20 males and 15 females from Blakeley Island, and 20 males and 15 females from Cypress Island, are respectively: total length 189, 183, 179; length of tail 87, 82, 79; hind foot 22.8, 22, 19.5; ear 19.4, 18.7, 19.5; weight 33, 29, 32 grams. _Distribution._--The San Juan Islands, San Juan and Skagit counties, in northern Puget Sound. =Peromyscus maniculatus austerus= (Baird) _Hesperomys austerus_ Baird, Proc. Acad. Nat. Sci. Philadelphia, 7:336, 1855. _Sitomys americanus austerus_ Allen, Bull. Amer. Mus. Nat. Hist., 5:192, August 18, 1893. _P[eromyscus]., austerus_ Bangs, Amer. Nat., 31:75, January 1, 1897. _Peromyscus maniculatus austerus_ Osgood, N. Amer. Fauna, 28:63, April 17, 1909.