MEADOW MOUSE 



Found in "San Diegan faunal district, from Mountain 

 Spring and mouth of Tiajuana River, San Diego County, 

 northwest to Gaviota Pass, Santa Barbara County, and 

 north to Bluff Lake, San Bernardino Mountains, San 

 Bernardino County. Vertical range from sea level up at 

 least to 9000 feet; zonal range Lower Sonoran to Canadian." 

 (Kellogg) 



Operarius Group 



Tundra Meadow Mouse. — Microtus operarius operarius 



(Nelson). 

 "Size small; tail short, densely haired; ears small and wholly 

 concealed in long winter fur; colors yellowish." (Bailey) 

 Upperparts (winter) dark, rich buff lightly sprinkled with 

 black on dorsal region; sides with less black; feet gray; 

 tail with faint blackish line on upper side, dirty whitish 

 on sides and undersurface, underparts pale buffy to creamy 

 white. Summer pelage darker yellow above, more buffy 

 below. Total length, 6.7 inches; tail vertebras, 1.6 inches; 

 hind foot, .8 inch. Found on "Barren grounds from 

 Bristol Bay, St. Michael, and Kowak River, Alaska, east 

 to Anderson River." (Bailey) 



Interior Meadow Mouse. — Microtus operarius endcecus Os- 

 good. 

 Resembling typical operarius in size and color, but with 

 slightly larger skull; distinguished from drummondi by 

 yellowish coloration, especially by buffy yellow underparts. 

 Total length, 6.7 inches; tail vertebrae, 1.5 inches; hind 

 foot, .8 inch. Found in east central Alaska. 



Macfarlane Meadow Mouse. — Microtus macfarlatii Merriam. 

 Resembling operarius but with shorter tail; pelage very 

 long in winter. Upperparts (winter) light buffy gray; feet 

 gray; tail bicolor, black and white; underparts whitish. 

 Summer pelage darker, more buffy. Tail vertebrae, 1.2 

 inches; hind foot, .75 inch. Found in "Tundra region of 

 Arctic America, east of the Mackenzie River." (Bailey) 



Yakutat Meadow Mouse. — Microtus yakutatensis Merriam. 

 Size of operarius, pelage dusky. Upperparts (summer) 

 dusky gray, with light wash of brownish dorsally; feet 

 gray; tail bicolor, black and whitish; underparts soiled 

 whitish to pale buffy. Total length, 6.5 inches; tail 

 vertebrce, 1.5 inches; hind foot, .8 inch. Found on "Main- 

 land of Alaska from Glacier Bay to Prince William Sound." 

 (Bailey) 



Kadiak Meadow Mouse. — Microtus kadiacensis Merriam. 

 Larger than yakutatensis; underparts white; ears small. 

 Upperparts (summer) yellowish brown sprinkled with a 

 few black hairs on dorsal region; feet gray; tail faintly 

 bicolor, black and whitish; underparts with wash of clear 

 white. Total length, 7.5 inches; tail vertebrae, 2 inches; 

 hind foot, .84 inch. Found only on Kadiak Island, Alaska. 



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