MEADOW MOUSE 



Subgenus Aulacomys 



Characterized by conspicuous side glands on adult males; a 

 musk-bearing anal gland; five plantar tubercles; large feet; 

 long tail; long and full pelage. 



Richardson Meadow Mouse. — Microtus richardsoni richard- 

 soni (De Kay). 

 Largest of the American Meadow Mice. Upperparts 

 (winter) grayish sepia sprinkled with black; sides paler; 

 feet silvery gray; tail bicolor, dusky and soiled whitish; 

 underparts washed with white. Total length, 9 inches; 

 tail vertebra, 2.5 inches; hind foot, 1.12 inches. Found in 

 the vicinity of Jasper House and Henry House, Alberta, 

 Canada. 



Big-footed Meadow Mouse. — Microtus richardsoni macropus 

 (Merriam). Plate XXX. 

 Resembling typical richardsoni but somewhat smaller. 

 Upperparts (summer) dark sepia mixed with black; sides 

 paler; feet dark gray; tail bicolor, sooty and whitish; 

 underparts washed with silvery white. Winter pelage 

 grayer above, with less black; more white below. Total 

 length, 8.8 inches; tail vertebrae, 2.8 inches; hind foot, 1.12 

 inches. Found in "Boreal Zone of the Rocky Mountains 

 from the Wasatch north to Canada, of the Wind River 

 Mountains of Wyoming, the Blue Mountains of Oregon, 

 and most of the intermediate ranges." (Bailey) 



Cascade Meadow Mouse. — Microtus richardsoni arvicoloides 

 (Rhoads). 

 Size of typical richardsoni, larger than macropus, darker 

 than either, Upperparts (summer): dark sepia mixed with 

 black; feet dusky gray; tail bicolor, blackish and soiled 

 whitish; underparts lightly washed with gray to silvery 

 white. Winter pelage darker above, more white below. 

 Total length, 9.4 inches; tail vertebrce, 3.2 inches; hind foot, 

 1. 16 inches: maximum size, total length, 10 inches; tail 

 vertebrce, 3.6 inches. Found in "Boreal Zone of the 

 Cascade Mountains, in Washington and Oregon." (Bailey) 



Subgenus Pedomys 



Characterized by presence of five plantar tubercles; long, 

 •coarse fur; side glands wanting or indiscernible; ears of 

 medium size. 



Prairie Meadow Mouse. — Microtus ochrogaster (Wagner). 

 Resembling pennsylvanicus in size, but tail shorter and 

 pelage coarser. Upperparts (winter) dark gray, grizzled 

 black and pale fulvous; sides paler; feet dusky; tail bi- 

 color, dusky and buffy; underparts pale cinnamon to 

 fulvous. Summer pelage darker. Total length, 6 inches; 



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