FIELD BOOK OF MAMMALS 



em California, and the adjoining part of Lower California." 

 (Osgood) 



California Pocket Mouse. — Perognathus californicus californi- 

 ciis Merriam. 

 Smaller than typical femoralis, but similar to it in charac- 

 ters of large ear and spiny rump and flanks. Color about 

 as in femoralis. Total length, 7.7 inches; tail vertebras, 

 4.1 inches; hind foot, .96 inch. Found in "Vicinity of San 

 Francisco Bay and south to Bear Valley, San Benito County, 

 where it meets the range of its subspecies dispar. ' ' (Osgood) 



Allen Pocket Mouse. — Perognathus californicus dispar Os- 

 good. 

 Resembling typical californicus but pelage softer, larger, 

 and paler. Upperparts bister; lateral line pinkish buff; tail 

 bicolor; underparts buffy white. Total length, 8.5 inches; 

 tail vertebrae, 4.7 inches; hind foot, 1.04 inches. Found in 

 "Coast valleys of California from San Bernardino to San 

 Benito County and north along the foothills of the west 

 slope of the Sierras to Placer County." (Osgood) 



Kern Pocket Mouse. — Perognathus californicus ochrus Osgood. 

 Resembling dispar but much paler. Upperparts pinkish 

 buff mixed with dusky to produce general effect of ecru 

 drab; lateral line pale pinkish buff; feet white; tail above, 

 light brown, below, white; underparts creamy white. Total 

 length, 8.5 inches; tail vertebras, 4.5 inches; hind foot, i 

 inch. Found in California in the "Lower Sonoran Zone 

 in the southern San Joaquin Valley, west to Cuyama Valley 

 and north to Alcalde, Fresno County." (Grinnell) 



Spinatus Group 



Spiny Pocket Mouse. — Perognathus spinatus spinatus (Mer- 

 riam. 

 Size medium; pelage harsh, with large conspicuous spines 

 on rump and scatteringly on flanks and sides as far as shoul- 

 ders; tail of medium length, crested; ears small and rounded; 

 lateral line reduced or absent. Upperparts drab brown, 

 hairs black-tipped; sides lighter than back; ears dusky; 

 tail pale brown above, whitish below; underparts buffy 

 white. Total length, 7.2 inches; tail vertebrae, 4 inches; 

 hind foot, .88 inch. Found in "Desert region of southern 

 California and northern Lower California." (Osgood) 



******* 

 The Pocket Mice are beautiful little rodents well charac- 

 terized by their mouse size and their external, hair-lined cheek- 

 pockets. The only other North American rodents with ex- 

 ternal cheek-pockets are much larger (rat size), and will not be 

 confused with Perognathus. 



These Mice are dwellers on the plains or deserts and are 

 never found in dense forests, although they do occur, to some 



310 



