Part 6

Type.--Adult female, skin and skull; No. 19658, Mus. Vert. Zool.; obtained on July 2, 1913, by Alfred C. Shelton, from Gualala, on the Sonoma County side of the Gualala River, Sonoma Co., California.

Range.--Coastal California from Point Reyes north to Point Arena.

Diagnosis.--Size large; average and extreme measurements of 3 topotypes are: total length, 141.7 (141-143); tail, 59 (54-63); hind foot, 17 (17-17). Color reddish in summer, somewhat grayer in winter.

Guide to subspecies

1. S. v. shumaginensis 2. S. v. obscurus 3. S. v. alascensis 4. S. v. soperi 5. S. v. isolatus 6. S. v. setosus 7. S. v. bairdi 8. S. v. permiliensis 9. S. v. yaquinae 10. S. v. pacificus 11. S. v. sonomae 12. S. v. longiquus 13. S. v. parvidens 14. S. v. monticola 15. S. v. neomexicanus 16. S. v. orizabae ]

Comparisons.--Differs from S. v. pacificus, with which it intergrades to the north, in average smaller size and somewhat darker color; differs from the sympatric S. v. vagrans in much larger size and more reddish color in both summer and winter.

Remarks.--This subspecies inhabits the Transition Life-zone below 300 feet, and occurs on moist ground in forests and beneath dense vegetation.

Marginal records.--CALIFORNIA: Point Arena (Grinnell, 1933:82); Monte Rio (Jackson, 1928:144); Inverness (Grinnell, 1933:82).

=Sorex vagrans pacificus= Coues

Sorex pacificus Coues, Bull. U. S. Geol. and Geog. Surv. Terr., 3 (3):650, May 15, 1877.

Sorex pacificus pacificus, Jackson, Jour. Mamm., 2:162, August 19, 1921.

Type.--Adult, sex unknown, skin and skull; No. 3266 U. S. Nat. Mus.; date of capture unknown; received from E. P. Vollum and catalogued on March 8, 1858; obtained at Ft. Umpqua, mouth of Umpqua River, Douglas Co., Oregon.

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.

Specimens examined.--Total number, 76.

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 vagrans yaquinae= Jackson

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.

Jackson (1928:141) remarked upon the possibility that intergradation between pacificus and yaquinae took place. He noted also the close resemblance between yaquinae and bairdi, and stated (loc. cit.) that specific affinity between the two might be demonstrated with more specimens. He had a series of eight specimens from Vida, Oregon, seven of which he assigned to S. o. bairdi and one to yaquinae. I have examined these specimens and find no more variation between the largest and the smallest than would be expected in any normally variable series of shrews. Vernon Bailey (1936:364) arranged yaquinae as a subspecies of pacificus without giving his reasons for so doing.