Clethrionomys gapperi (Vigors, 1830) . Zool. J., 5:204.

TYPE LOCALITY: Canada, Ontario, between York (=Toronto) and Lake Simcoe .

DISTRIBUTION: From Labrador to N. British Columbia (Canada), south in the Appalachians to N. Georgia; Great Lakes, Northern Plains, and Rocky Mtns. (New Mexico and Arizona) to Columbia River in Washington (U.S.A.).

COMMENT: Includes occidentalis and caurinus; see Johnson and Ostenson, 1959, J. Mammal., 40:571-577, Cowan and Guiguet, 1965, The Mammals of British Columbia, Br. Columbia Prov. Mus. Handbook, 11: 1-413, and Hall, 1981:780, 782-783. Closely related to Eurasian glareolus; captive mating produces fertile hybrids, but of reduced fertility; see Grant, 1974, J. Zool. Lond., 174:245-254. Youngman, 1975, Mammals of the Yukon Terr., Nat. Mus. Can. Publ. Zool., 10:85, considered gapperi and rutilus conspecific; but see Nadler et al., 1978, Can. J. Zool., 56(7): 1564-1575, and Hall, 1981:778-784; also see comment under rutilus . Reviewed by Merritt, 1981, Mamm. Species, 146:1-9.

ISIS NUMBER: 5301410008072001001 as C. gapperi .

ISIS NUMBER: 5301410008072003001 as C. occidentalis.