Peromyscus leucopus (Rafinesque, 1818) . Am. Mon. Mag., 3:446.

TYPE LOCALITY: USA, Kentucky, "pine barrens," presumably near mouth of Ohio River .

DISTRIBUTION: C and E USA, excluding Florida; northwards to S Alberta and to S Ontario, Quebec and Nova Scotia, Canada; southwards to N Durango and along Caribbean coast to Isthmus of Tehuantepec and NW Yucatan Peninsula, Mexico.

SYNONYMS: affinis, amnwdytes, arboreus, aridulus, arizonae, brevicaudus, campestris, canus, castaneus, caudatus, cozulmelae, easti, emmonsi, flaccidus, fuscus, incensus, lachiguiriensis, mearnsii, mesomelas, michiganensis, minnisotae, myoides, musculoides, noveboracensis, ochraceus, texanus, torniilo.

COMMENTS: Revised by Osgood (1909). Distinctive northeastern ( leucopus) and southwestern (texanus) cytotypes reported (R. J. Baker et al., 1983b), with introgression across hybrid zone in central Oklahoma (Nelson et al., 1987; Stangl, 1986; Stangl and Baker, 1984a). Genetic variation investigated by Browne (1977) —also see above account of P. gossypinus . See Lackey et al. (1985, Mammalian Species, 247).