1918 | Taylor: Revision of the Rodent Genus Aplodontia 463 
character of the subspecies, is subject to considerable variation (text 
figs. I, J, K), and is more apparent in specimens from Lake Cushman 
than in those from Quiniault Lake. Specimens from Steilacoom (no. 
2476, U.S. Nat. Mus., skull only) and Fort Steilacoom (no. 278, U. 8. 
Nat. Mus., part of skull inside skin), here referred to olympica, might 
be referred to rufa with equal propriety. 
Aplodontia rufa columbiana Taylor 
Northern Aplodontia 
Aplodontia californica columbiana Taylor (1916c), pp. 499-501. 
Type.—Male adult ; no. 1899, Coll. E. A. and O. Bangs, Mus. Comp. 
Zool.; Roab’s Ranch, Hope, British Columbia; June 14, 1894; col- 
lected by W. C. Colt; stuffed skin with skull and jaws in good econdi- 
tion, except skin of foreleg injured in trap, and skull with left audital 
tube, region of foramen magnum, and hamulars, somewhat injured. 
Geographic Range.—Vicinity of Hope, British Columbia, south in 
the Cascade Mountains of Washington; probably intergrading with 
Aplodontia rufa rainiert between the international boundary and 
Mount Rainier. 
Specimens Examined—Total number 11, from the following 
localities : 
British Columbia: Yale Provincial District—Lake House, near Hope, 4; 
Roab’s Ranch, Hope, 5. Washington: Skagit County—Head of Cascade River, 2. 
Cranial Characters—Skull heavy and large (see measurements 
below) ; for example, on basis of tables of measurements, furnishing 
maximum for the genus in length of nasals, zygomatic width, mastoid 
width, and greatest length of mandible; averages of length of nasals 
and zygomatic width exceeding the maximum in any other form; zygo- 
matic arches moderate and, looking down upon them from above, trans- 
versely expanded posteriorly ; temporal lines or ridges tending to be 
closely approaching, though never forming a distinct sagittal crest ; 
dorsal outline of skull comparatively straight; audital tubes small 
ealibered, dorso-ventral diameter tending to exceed anteroposterior 
diameter, tube thus appearing as if pinched anteroposteriorly. 
External Characters—Above, in summer skins, near light pinkish 
cinnamon, in some specimens as pale as light ochraceous-buff, in others 
as dark as pinkish cinnamon, grizzled with many blackish and some- 
times a few whitish-tipped hairs; number and degree of concentration 
of black hairs on back variable ; underparts showing faint brown wash, 
