The size of the wandering shrew varies from small in the subspecies _monticola_ and _vagrans_ to large in the subspecies _pacificus_. The tail makes up from a little more than a third to almost half of the total length. The color pattern ranges from tricolored through bicolored to almost monocolored. Color ranges from reddish (Sayal or Snuff Brown) to grayish in summer pelage and from black to light gray in winter. Diagnostic dental characters include: 3rd upper unicuspid smaller than 4th, and unicuspids, except 5th, with a pigmented ridge extending from near apex of each tooth medially to cingulum and sometimes ending as internal cusplet. _S. vagrans_ differs from members of the _ornatus_ group in less flattened skull, and in more ventrally situated foramen magnum that encroaches more on the basioccipital and less on the supraoccipital. The wandering shrew differs from _S. trowbridgii_ and _S. saussurei_ in the dental characters mentioned above. These dental characters also serve to distinguish _S. vagrans_ readily from _S. cinereus_, _S. merriami_, and _S. arcticus_ which may occur with _vagrans_. The large marsh shrew and water shrew, _S. palustris_ and _S. bendiri_, can be distinguished at a glance from _S. vagrans_ by larger size and darker color. [Illustration: FIG. 15. Diagrammatic representation of the probable phylogeny of _Sorex vagrans_ and its near relatives.] In the following treatment of the 29 subspecies of _Sorex vagrans_, the subspecies are arranged in geographic sequence, beginning with the southernmost large subspecies on the California coast and proceeding clockwise, north, east, south, and then west back to the starting point. =Sorex vagrans sonomae= Jackson _Sorex pacificus sonomae_ Jackson, Jour. Mamm., 2:162, August 19, 1921. _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. [Illustration: FIG. 16. Probable geographic ranges of 16 subspecies of _Sorex vagrans_. 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_ ]