112 Jferriaui N~ew Species of TJunnomys. 



mata more squarely spreading; premaxilhe shorter and broader poste 

 riorly; bulla 1 less swollen; incisors narrower. 



Measurement*.- Type specimen ( $ ad.): total length 191'; tail verte 

 brae 62; hind foot 25. Average of 6 specimens from type locality: total 

 length 192; tail vertebra 1 58; hind foot 25. 



Thomomys myops sp. nov. 



Type from Conconully, east base Cascade Range, State of Washington. 

 No. 91,06(5, 9 au "-- ^ S- National Museum, Biological Survey Collec 

 tion. September 11, 1897. J. Alden Loring. Original No. 4050. 



Characters. Size small; color and external characters generally as in 

 T.fuscus; skull peculiar. 



Color. Upperparts dull pale rufous brown: underparts buff}- ochra- 

 ceous, the dark slate underfur showing through: throat, chin, and feet 

 whitish; nose, sides of mouth, ring round eye, and earpatch dull plum 

 beous, the earpatch darkest. 



Cranial characters. Skull in general similar to that of quadratus, but 

 zygomata less quadrate and posterior root shorter: nasals broader, trun 

 cate posteriorly, and ending on same plane as premaxillae, which are 

 remarkably short and truncate posteriorly; bullae about as in quadratus 

 less swollen than in fuscus; under jaw rather massive, about as in 

 quadratus decidedly heavier than iufuscus. 



Measurements. Type specimen (9 ad.): total length 197; tail verte 

 bras 63; hind foot 26. Average of 7 specimens from type locality: total 

 length 184; tail vertebrae 58; hind foot 24.5. 



Thomomys leucodon navus subsp. nov. 



Type from Red Bluff, California. No. 57,791, $ ad., U. S. National 

 Museum, Biological Survey Collection. December 26, 1893. C. P. 

 Streator. Original No. 3462, 



Characters. Similar to leucodon but much smaller; incisors projecting 

 forward, their faces yellow instead of white; upperparts paler and 

 brighter fulvous: underparts buffy ochraceous instead of fulvous. 



Cranial characters. Skull small but very strong and ivory-like in text 

 ure; zygomata broadly spreading, broadest posteriorly; nasals cuneate, 

 usually notched behind. 



Measurements. Type specimen ( $ ad.): total length 200: tail verte 

 brae 67; hind foot 27. Average of 8 specimens from type locality: total 

 length 196; tail vertebrap 65; hind foot 27. 



Thomomys uinta sp. nov. 



Type from Uinta Mountains, Utah. Altitude 10,000 feet. No. |^j, 

 $ ad., U. S. National Museum, Biological Survey Collection. June 6, 

 1890. Vernon Bailey. Original No. 1262. 



