1915.1 



THOMOMYS FULVUS GEOUP. 



87 



THOMOMYS MEARNSI Bailey. 

 Mearns Pocket Gopher. 



(PI. VI, fig. 4.) 



Thomomys meamsi Bailey, Proc. Biol. Soc. Washington, XXVII, 117, July 10, 1914. 



Type. — Collected at Gray's Ranch, in Animas VaUey, southwest 

 comer of New Mexico (about 20 miles north, of the Mexican line), 

 by E. A. Goldman, August 10, 1908. Type specimen in U. S. Nat. 

 Mus.; Biological Survey collection. 



Distribution. — Kjiown only from type locality (fig. 7). 



Characters. — Slightly smaller than fulvus; less dusky in color; 

 skull short and wide with very slender, projecting incisors; ears 

 medium; mammae in 4 pairs, inguinal 2-2, pectoral 2-2. 



Color. — Summer pelage: Upperparts dull cinnamon or Ught tawny, 

 with blackish nose and ear patches; underparts pale cinnamon; tail 

 buffy gray; feet whitish. 'Winter pelage: Evidently more grayish as 

 indicated by some worn patches of old long fur. 



Sicull. — Short and wide, with arched zygomata, short braincase, 

 short rostrum, and protruding upper incisors; bullse very short and 

 round; pterygoids V-shaped; nasals short and truncate or shghtly 

 emarginate; anterior base of zygoma convex against frontal and 

 premaxillse. Dentition: Incisors very slender, pale, and protruding 

 far beyond nasals; distinctly grooved. 



Measurements. — Type: Total length, 220; tail vertebrae, 67; hind 

 foot, 31. Topotype ($ ad.): 201, 65, 29. Sicull (of type): Basal 

 length, 37; nasals, 12.4; zygomatic breadth, 26; mastoid breadth, 

 21.5; interorbital breadth, 6; alveolar length of upper molar series, 7. 



Remarks. — This seems to be a local form in the bottom of the 

 Animas Valley, somewhat resembling nelsoni but not of the umhrinus 

 group. The four pairs of mammse place it in the fulvus group, but 

 it seems to be distinct from the surrounding toltecus. Specimens 

 were taken around the moist edges of a large marsh on the Gray 

 Ranch and the moist, alkaline soil may be the environmental factor 

 that has produced a local form in the midst of wide deserts. It is 

 quite probable that the form occupies similar situations aU along 

 the Animas and San Simon YaUeys. 



Specimens examined. — Four, from type locality. 



THOMOMYS BAILEYI Merriam. 

 Sierra Blanca Pocket Gopher. 



(PL VI, fig. 7.) 



Thomomys haileyi Merriam. Proc. Biol. Soc. Washington, XI Y. 109, July 19, 1901. 



Type. — Collected at Sierra Blanca, El Paso County, Texas, by 

 Vernon Bailey, December 28, 1889. The type and topotypes were 

 caught all around the railway station where the Texas Pacific joins 

 the Southern Pacific. Type specimen in U. S. Nat. Mus., Biological 

 Survey collection. 



