_Range._--Coast of California and Oregon from Mendocino north to Gardiner.
_Diagnosis._--Size large, largest of the species; average and extreme measurements of 8 specimens from Orick, Humboldt Co., California, are: total length, 143.1 (134-154); tail, 65.5 (59-72); hind foot, 17.5 (16-19). Color reddish in summer, browner or grayer in winter.
_Comparisons._--See account of _S. v. sonomae_ for comparison with that subspecies; averaging larger in all dimensions than _S. v. yaquinae_ with which it intergrades to the north; much larger and has more reddish than the sympatric _S. v. vagrans_.
_Remarks._--This subspecies occurs in the Canadian and Transition life-zones below 1500 ft. where there is found moist ground in or adjacent to heavy forests.
OREGON: _Douglas Co._: Umpqua, 1 BS. _Coos Co._: Marshfield, 1 BS; Myrtle Point, 1 BS. _Josephine Co._: Bolan Lake, 1 SGJ.
CALIFORNIA: _Del Norte Co._: Smith River, 2 BS; Gasquet, 4 BS; Crescent City, 17 BS. _Humboldt Co._: Orick, 13 BS; 1 mi. N Trinidad, 18 FC; Trinidad Head, 1 BS; Carson's Camp, Mad River, Humboldt Bay, 5 BS; Arcata, 3 BS; Cape Mendocino, 2 BS; 5 mi. S Dyerville, 1 BS. _Mendocino Co._: Mendocino, 6 BS.
_Marginal Records._--OREGON: Marshfield; Umpqua. CALIFORNIA: Gasquet; 5 mi. S Dyerville; Mendocino, thence up coast to point of beginning.
_Sorex yaquinae_ Jackson, Proc. Biol. Soc. Washington, 31:127, November 29, 1918.
_Sorex pacificus yaquinae_, V. Bailey, N. Amer. Fauna, 55:364, August 29, 1936.
_Type._--Adult female, skin and skull; No. 73051 U. S. Biol. Surv. Coll., obtained on July 18, 1895, by B. J. Bretherton, from Yaquina Bay, Lincoln Co., Oregon.
_Diagnosis._--Size large for the species; average and extreme external measurements of 11 specimens from Oakridge, Lane Co., Oregon, are: total length, 125.3 (11-136); tail, 55.1 (49-61); hind foot, 14.9 (14-16). Color reddish in summer, browner or grayer in winter.
_Comparisons._--See account of _S. v. pacificus_ for comparison with that subspecies. Larger and more reddish than _S. v. bairdi_ with which it intergrades to the north and east. Much larger and more reddish than the sympatric _S. v. vagrans_.
_Remarks._--The name _yaquinae_ actually applies to a population of intergrades between _pacificus_ and _bairdi_. There is much variation over the range of the subspecies, and individuals from the western and southern parts are larger than those from the west slope of the Cascades. Specimens from Vida and McKenzie Bridge are smaller than those from Mapleton, Mercer, and the type locality but still seem closer to _yaquinae_ than to topotypes of _bairdi_. Between Marshfield and Umpqua on the one hand, and the Columbia River and the Cascade Mountains on the other, the size of _Sorex vagrans_ decreases quite rapidly from the large_ pacificus_ to the smaller _permiliensis_. Size decreases less rapidly northward along the coast than it does eastward toward the mountains; consequently, at any given latitude, coastal shrews are larger than mountain shrews. In this area of rapid change in size it is difficult to draw subspecific boundaries between _pacificus_, _yaquinae_, and _bairdi_, and this must be done somewhat arbitrarily.