122 ONYCHOMYS. 



Ci>/or. Similar to O. hmgicaiufiis. Above grayish vinaceous buff; 

 dorsal part darker; beneath white. Tail bicolor, dark above, lighter 

 below. 



Measurements. Total length, 147: tail vertebra?, 48; hind foot, 

 iS: ear. 12. 



156. torridus. [Onychomys). Coues, Proc. Acad. Nat. Scien. Phil., 

 1874, p. 1S3. 



Type locality. Camp Grant, Arizona. 



Geogr. Distr. Between Mississippi River and Rocky Mountains. 

 Upper Missouri. Red River of the North, Wyoming, Kansas, Ari- 

 zona. 



Geni. Char. Similar to O. leucogaster, tail longer; ears longer; 

 colors more yellowish. 



Color. General color more yellowish than O. leucogaster, no 

 dorsal stripe, feet and under parts tawny white. Tail above dusky, 

 beneath white. 



Measurements. Total length, 143; tail vertebra?, 50; hind foot, 

 20; ear, 18. 



a —arenieolo. [Onyc/wmys), Mearns, Proc. U. S. Nat. Mus., vol. xix, 

 1897, p. 139. 



Type locality. Rio Grande, near El Paso, Texas. 



Geogr. Distr. Northwestern Texas. 



Genl. Char. Similar to O. torridus, but slightly smaller, with 

 relatively smaller ears and a very much paler coloration. 



Color. Above drab gray, inclining to fawn color on sides; dor- 

 sals area with very little admixture of black-edged or black-tipped 

 hairs, with a conspicuous tuft of white hairs at anterior base of ears: 

 dark spot on anterior band of ear, drab (not black); whiskers more 

 white than black; under parts, feet and end of tail white; basal two- 

 thirds of upper side of tail drab, some of the hairs with hoary tips. 



Measurements. Total length, 137; tail vertebrae, 53 (to end of 

 pencil. 57); hind foot, 21. Skull, 25.5 by 13.5. (Mearns, 1. c.) 



b.— prepallidus. {Onyehomys), Mearns, U. S. Nat. Mus., vol. xix, 1897, 

 p. 140. 



Type locality. Colorado River at Monument No. 204, Mexican 

 boundary line. 



Geogr. Distr. Gila City, across Yuma and Colorado Deserts to 

 Coast Range of mountains. 



Genl. Char. Larger than O. torridus, with relatively larger ears, 

 longer tail and a much paler coloration. 



Color. Above drab-gray, becoming more cinereous anteriorly; 

 sides and rump barely tinged with fawn color; dusky line on basal 



