FIELD BOOK OF MAMMALS 



parts white. Total length, 4.7-5.6 inches; tail vertebrae 

 2-2.6 inches; hind foot, .65 inch. Found in "San Luis 

 Valley, Colo." (Howell) 

 Desert Harvest Mouse. — Reithrodontomys megalotis megalotis 



(Baird). 

 Larger than montanus. Total length, 5.1-5.8 inches; tail 

 vertebrae, 2.6-3.1 inches; hind foot, .7 inch; ear, .5 inch. 

 Upperparts, summer, light ochraceous buff mixed with 

 blackish brown, darkest along dorsal line; ears drab, with a 

 few ochraceous buff hairs about base; underparts and feet 

 white. Found "From northern Nevada and southern Idaho 

 south to Zacatecas, Mexico; occupying the greater part of 

 Nevada, Arizona, and Utah (except eastern part) ; southern 

 New Mexico ; western Texas (west of Pecos River) ; desert 

 regions of southern and northeastern California. ..." 

 (Howell) 

 Aztec Harvest Mouse. — Reithrodontomys megalotis aztecus 



(Allen). 

 Like typical megalotis in size and color, but ears larger, .5-.6 

 inch from notch. Found in "Northern New Mexico, north- 

 eastern Arizona, southeastern Utah, and western Colorado, 

 north to Grand Junction and Rifle." (Howell) 

 Prairie Harvest Mouse. — Reithrodontomys megalotis dychei 



(Allen). 

 Blacker and with more intensely ochraceous upperparts than 

 typical megalotis, ears smaller, tail shorter. Total length, 

 5.2-5.6 inches; tail vertebree, 2.3-2.6 inches; hind foot, .6-.7 

 inch; ear from notch, .45 inch. Found in "Greater part of 

 Kansas, Nebraska, Iowa, Missouri, and South Dakota; 

 southern North Dakota; southeastern Montana; eastern 

 Colorado and eastern Wyoming." (Howell) 

 Dusky Harvest Mouse. — Reithrodontomys megalotis nigrescens 



Howell. 

 Blacker and less buffy above than typical megalotis. Up- 

 perparts, winter, pale ochraceous buff mixed with blackish, 

 darkest dorsally ; in summer browner than in winter. Total 

 length, 5.6-6.1 inches; tail vertebras, 2.5-3 inches; hind foot, 

 .65 inch. Found in "Eastern Oregon and western Idaho; 

 north to Prescott, Wash., south to Bieber, Cal." (Howell) 

 California Harvest Mouse. — Reithrodontomys megalotis longi- 



caudus (Baird). 

 Darker and smaller than typical megalotis, with less gray 

 and more ochraceous than nigrescens. Upperparts in winter 

 mixed blackish and ochraceous buff. Total length, 5.2-5.8 

 inches; tail vertebrae, 2.8-3.2 inches; hind foot, .65 inch. 

 Found in "Greater part of western California, east to the 

 foothills of the Sierra Nevada, San Bernardino, and San 

 Jacinto Ranges; north to Grants Pass, Greg., and south into 

 northwestern Lower California to about latitude 32°." 

 (Howell) 



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