FIELD BOOK OF MAMMALS 



Species and Subspecies of the Genus Aplodontia. 



Brown Mountain Beaver. — Aplodontia rufa rufa (Rafinesque) . 

 As described above. Found in "Neighborhood of the 

 Columbia River, in western Oregon, interiorly on the 

 Pacific side of the Cascades; thence southward in a belt of 

 unknown width to Mount Mazama in southern Oregon 

 and the Siskiyou-Trinity district in northern California; 

 northward to Puget Sound and the Chilliwack-Sumas 

 region in southwestern British Columbia. Altitudinal 

 range, from sea level in the Puget Sound district to 6,500 

 feet in the Siskiyou-Trinity Mountains of northern Cali- 

 fornia; zonal range. Transition and Canadian." (Taylor) 



Olympic Mountain BesLwer.— Aplodontia rufa olympica (Mer- 

 riam). 

 "Above, in summer specimens, pinkish cinnamon to light 

 ochraceous-buff, often with something of a grayish cast; 

 the whole grizzled with more or less of an admixture of 

 black hairs; head and face brownish or grayish; under 

 parts grayish with a faint wash of pinkish buff or cinnamon- 

 buff. " (Taylor) Total length, 14 inches; hind foot, 2.0 

 inches. "Geographical Range. — Northwestern Washing- 

 ton, vicinity of Olympic Mountains, intergrading with 

 Aplodontia rufa rufa in the vicinity of Steilacoom, southern 

 Puget Sound." (Taylor) 



Northern Mountain Beaver. — Aplodontia rufa columhiana 

 (Taylor). 

 Upperparts varying in individuals from light pinkish 

 cinnamon to pinkish cinnamon grizzled with blackish 

 and sometimes a few whitish-tipped hairs; underparts 

 faintly washed with brown over pale drab gray; males 

 usually with irregular white patches on underparts. Total 

 length, 17 inches. Found in "Vicinity of Hope, British 

 Columbia, south in the Cascade Mountains of Washington; 

 probably intergrading with Aplodontia rufa rainieri be- 

 tween the international boundar}^ and Mount Rainier." 

 (Taylor) 



Mount Rainier Mountain Beaver. — Aplodontia rufa rainieri 

 (Merriam). 

 Grayer than typical rufa, slightly larger. Upperparts 

 light ochraceous buff, liberally sprinkled with blackish 

 hairs which may be tipped with silvery white; back blacker 

 than sides; underparts plumbeous, with whitish markings 

 which are usually most conspicuous on throat. Total 

 length, 15 inches; hind foot, 2.5 inches. Found only on 

 Mount Rainier, Washington. 



Pacific Mountain Beaver. — Aplodontia rufa pacifica (Mer- 

 riam). Plate XXXIV. 

 With more gray on head than in olympica and more con- 

 centration of blackish on dorsal region. Upperparts cinna- 

 mon to pinkish cinnamon, thickly sprinkled with glossy 



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