POCKET MOUSE 



Parvus Group 



Oregon Pocket Mouse. — Perognathus parvus parvus (Peale). 

 Large in size; tail long and slightly tufted; ears medium; 

 sole of hind foot hairy on upper fourth; occurring in two 

 color phases, with intermediates. Gray phase: upperparts 

 pale slaty buff sprinkled with black; sides paler than back; 

 lateral line buff; tail above dusky, laterally buff, below 

 white. Underparts white, belly darker. Buff phase like 

 gray, but general tone buffy. Total length, 6.8 inches; tail 

 vertebrae, 3.6 inches; hind foot, .9 inch. Found in "Valley 

 of the Yakima River, Washington, and thence southward to 

 central and southeastern Oregon. Upper Sonoran Zone." 

 (Osgood) 



Idaho Pocket Mouse. — Perognathus parvus idahoensis Gold- 

 man. 

 Large; darkest of the subspecies of parvus. Upperparts 

 light vinaceous buff heavily mixed with black, especially 

 dark on lower back which is blackish; lateral line almost 

 clear buffy; ears blackish with conspicuous white spots at 

 base; tail above, mixed black and buffy, nearly black at tip, 

 below, pale buffy; underparts dull whitish on chin, throat, 

 and inner sides of forearms, light ochraceous buff on belly 

 and insides of hind limbs; heels black. Total length 7.5 

 inches; tail vertebrae, 4 inches; hind foot, .96 inch. Found 

 only near Arco, Blaine County, southern Idaho; limits of 

 range unknown. 



Coues Pocket Mouse. — Perognathus parvus mollipilosus 

 (Coues). 

 Smaller than typical parvus; ears larger; markings more in- 

 tense; coloration darker. Upperparts warm ochraceous 

 buff, liberally sprinkled with black; a distinct lateral line; 

 underparts white, belly tawny. Total length, 6.7 inches; 

 tail vertebrae, 3.5 inches; hind foot, .9 inch. Found in 

 "Great Basin extension of northeastern California, north 

 to Klamath Basin, Oregon. Upper Sonoran Zone, except 

 on Mount Shasta, where it ascends to the Boreal." (Os- 

 good) 



Great Basin Pocket Mouse. — Perognathus parvus oUvaceus 

 (Merriam). 

 Resembling typical parvus but pelage softer and lighter in 

 color. Upperparts bright cinnamon-buff; finely sprinkled 

 with black; lateral line and spot below ear conspicuous; 

 underparts white, belly sometimes buffy. Total length, 

 males, 7 inches; tail vertebrae, 3.8 inches; hind foot, .88 

 inch. Found in "Upper Sonoran Zone throughout the 

 Great Basin, from northern Utah and southern Idaho south- 

 west to Owens Valley, California, and west to southern Ore- 

 gon and northeastern California." (Osgood) 



Uinta Pocket Mouse. — Perognathus parvus clarus Goldman. 

 Somewhat larger than typical parvus and paler in color. 



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