FIELD BOOK OF MAMMALS 



underparts pale buffy gray, throat white. Upperparts (black 

 phase) bluish black to plumbeous; underparts like upper 

 except for white on throat and usually on feet. Total 

 length, males, ii.o inches, females, 10.2; tail vertebras, 

 males, 3.6 inches, females, 3.3; hind foot, males, 1.5 inches, 

 females, 1.4. Found in "Valleys of central and northern 

 Nevada and southeastern Oregon, from Austin and Love- 

 locks, Nev , north to Alvord Lake, Greg." (Bailey) 



Subgenus Megascapheus 



Characterized by large size ; mammee in four pairs (inguinal, 

 2-2; pectoral, 2-2) \ and by cranial characters. 



Camas Pocket Gopher or Camas Rat. — Thomomys hulbivorus 

 (Richardson). Plate XX VL 

 Very large in size, largest species of the genus; claws of front 

 feet relatively small and weak; external ears greatly reduced, 

 a mere thickened rim ; tail practically naked ; color very dark, 

 Upperparts (winter) dark sooty brown; blackish on nose and 

 ears, white on feet (in streaks or blotches), chin, throat, and 

 a small spot at base of tail below; underparts like upperparts, 

 but with darker underfur showing through. Summer pelage 

 like winter, but washed with rusty brown above and below. 

 Total length, males, 12.0 inches, females, 10.8; tail vertebras, 

 males, 3.6 inches, females 2>-'2,; hind foot, males, 1.7 inches, 

 females, 1.6. Found in "Willamette Valley, Greg., from 

 Portland and Forest Grove south to Eugene ; west to Grand 

 Ronde." (Bailey) 



The Pocket Gopher is easily distinguished from other 

 rodents by its fur-lined cheek-pockets, broad head, strong 

 claws, and fossorial habit. The only other American rodents 

 with external cheek-pockets are the Pocket Mice and Pocket 

 Rats which have no such specializations for living an under- 

 ground existence and bear little resemblance to Pocket 

 Gophers. 



The Western Pocket Gophers {Thomomys) differ from the 

 Eastern Pocket Gophers of the Mississippi Valley (Geomys) 

 in showing no very distinct grooving on the incisors ; otherwise 

 the two genera are very much alike superficially. 



Pocket Gophers are abundant over much of western North 

 AmericH, and yet the animals themselves are seldom seen by 

 the average observer. This is because the Gopher spends 

 almost its entire existence underground and appears at the 

 mouth of its burrow for only an instant, when it throws out 



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