The cinereous shrew ranges over most of Alaska, Canada and the northern half of the United States. A number of subspecies have been described, of which two have been reported from Washington. The cinereous shrew is of medium size and difficult to distinguish from the dusky and wandering shrews, especially in eastern Washington, without studying the skulls. In _cinereus_ the fourth unicuspid tooth is smaller than the third; in _vagrans_ and _obscurus_ it is larger. The relatively narrow rostrum of _cinereus_ also serves to separate it from the other two species. The cinereous shrew seems to be less restricted to the vicinity of streams and marshes than _Sorex vagrans_, resembling _Sorex obscurus_ and _Sorex trowbridgii_ in this respect. In Washington it seems to be rare and has not been taken by the writer. Published records for _Sorex c. cinereus_ indicate that this race is, in Washington, confined to mountainous areas. The coastal race, _streatori_, seems to be confined to the humid area. =Sorex cinereus cinereus= Kerr _Sorex arcticus cinereus_ Kerr. Anim. Kingd., p. 206, 1792. _Sorex cinereus cinereus_ Jackson. Jour. Mamm., 6: 56, February 9, 1925. _Type._--None. Name based on the account of a shrew seen at Fort Severn, Canada, by J. R. Forster in 1772. _Racial characters._--Small size and pale color. _Measurements._--Seven males and 8 females from Indian Point Lake, British Columbia, average, respectively: total length 99, 95; length of tail 43.5, 42.2; hind foot 12.7, 12.3. _Distribution._--Northeastern Washington (Metaline and Loon Lake, Jackson, 1928: 49) and the Cascades from Whatcom Pass (Jackson, 1928: 55) southward to Conrad Meadows (Jackson, 1928: 49). There is a specimen in the collection of the California Academy of Sciences, from Mt. Rainier. _Remarks._--This is the most wide-ranging subspecies of shrew, being recorded from Alaska, 10 Canadian provinces and 26 states (Jackson, 1928: 46-50). In the more northern and eastern parts of its range it is sometimes the commonest shrew. [Illustration: FIG. 27. Distribution of the cinereous shrew in Washington. A. _Sorex cinereus cinereus._ B. _Sorex cinereus streatori._] =Sorex cinereus streatori= Merriam _Sorex personatus streatori_ Merriam. N. Amer. Fauna, 10:62, December 31. 1895. _Sorex cinereus streatori_ Jackson. Jour. Mamm., 6:56. February 9, 1925. _Type._--Obtained at Yakutat, Alaska, by C. P. Streator on July 9, 1895; type in the United States National Museum. _Racial characters._--Larger and darker than _Sorex cinereus cinereus_. _Measurements._--Five females from Alta Lake, British Columbia, average: total length 103; length of tail 45; hind foot 12.5.