GEOMYID^ 137 



Thomomys monticolus pinetorum Merriam. (Of the 



pines.) 



PINE-WOODS POCKET-GOPHER. 



Similar to monticolus but smaller, skull shorter with broader 

 zygomata ; color paler ; above pale fulvous ; nose dusky. 



Type locality, Sisson, Siskiyou County, California. 



Common around the base of Mount Shasta, grading- grad- 

 ually into monticolus on the higher parts of the mountain. 



Thomomys alpinus Merriam. (Alpine.) 



ALPINE POCKET-GOPHER. 



Similar to fulvus. Light pelage; above sepia or drab brown 

 suffused with fulvous ; below plumbeous washed with ochraceous 

 buff. Dark Pelage; plumbeous tipped with russet brown. Skull 

 small, rounded ; nasals rather short ; zygomata wide. 



Length about 220 mm. (8.65 inches); tail vertebrae 63 

 (2.50); hind foot 30 (1.20). 



Type locality, Cottonwood Meadows, Mount Whitney, Cali- 

 fornia. 



Common in the high southern Sierra Nevada. 



Thomomys perpallidus Merriam. (Very pale.) 



PALLID POCKET-GOPHER. 



Very pale; varying (principally with locality) from- yellow- 

 ish drab to ochraceous buff, cream' buff or grayish white; below 

 dull white, the hairs sometimes white to^ the roots but more often 

 pale plumbeous basally; mouth parts more or less brown; skull 

 rather large, smooth; rostrum rather wide; nasals long, depressed, 

 rather narrow, squarish posteriorly; frontal flat, often slightly 

 concave; interparietal about as long as wide, the front outline 

 subcircular. 



Length about 233 mm. (9.15 inches) ; tail vertebrae 85 

 (3.35) ; hind foot 33 (1.30) ; ear from crown 6 (.24). 



