332 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4TH SER. 
Range—Tree-yucca belt (high Lower Sonoran and low 
Upper Sonoran zones) in vicinity of Walker Pass, Kern 
County (Mus. Vert. Zool.). 
Perognathus alticola Rhoads 
White-eared Pocket Mouse 
Original description—Perognathus alticolus Rhoads, Proc. 
Acad. Nat. Sci. Phila., December, 1893, p. 412. 
Type locality—Squirrel Inn, near Little Bear Valley, San 
Bernardino Mountains, San Bernardino County, California. 
Range—Known only from the lower Transition zone in the 
near vicinity of the type locality (Stephens, Calif. Mammals, 
1906, p. 166). 
Perognathus baileyi baileyi Merriam 
Bailey Pocket Mouse 
Original description—Perognathus baileyi Merriam, Proc. 
Acad. Nat. Sci. Phila., September 27, 1894, pp. 262, 263. 
Type locality—Magdalena, Sonora, Mexico. 
Range—Agave belt of Upper Sonoran zone at Mountain 
Spring, near Mexican boundary, San Diego County (Mus. 
Vert. Zool.). 
Perognathus formosus Merriam 
Long-tailed Pocket Mouse 
Original description—Perognathus formosus Merriam, N. 
Amer. Fauna, 1, October, 1889, pp. 17, 18. 
Type locality—St. George, Washington County, Utah. 
Synonym—Perognathus mesembrinus Elliot, Field. Col. 
Mus., zool. ser., 3, December, 1903, p. 251 (type from Palm 
Springs, Colorado Desert, Riverside County, California). 
Range—Upper and Lower Sonoran zones in portions of the 
Mohave desert region; northwest through the Inyo region at 
least to Lone Pine and the Inyo Mountains; southwest to the 
north base of the San Bernardino Mountains and to La Puerta, 
eastern San Diego County; southeast to the Colorado River 
at Pilot Knob, Imperial County (Mus. Vert. Zool.; Osgood, 
N. Amer. Fauna, 18, 1900, p. 41). 
