i!"-* I Grinnell: Four New Pocket Gophers from California 313 



Thomomys diaboli, new species 

 Diablo Gopher 



Type. — J adiil1 (contained five embryos), no. 14165, Mus. Vert. 

 Zool.; Sweeney's Ranch, in hills of Diablo Range twenty-two miles 

 south of Los Banns, Merced County, California; April 2, 1911; col- 

 lected by ('. H. Richardson and 11. A. Can-; original im. 108. 



Diagnosis. — A member of the bottai series of gophers; smallest of 

 all the forms so far known from west-central California; nearest in 

 color to Thomomys angularis angularis Merriam, but slightly darker 

 brown, especially beneath; other characters: small ears and feet, very 

 weak and narrow rostrum, small teeth, moderately projecting incisors, 

 and short nasals. 



Material. — Seven specimens (nos. 14160-14165, 14696) from the 

 type locality, as above; one (no. 16676) from top of divide on wagon 

 road. 3000 feel altitude, in the Temblor Range, eleven miles west- 

 northwest of McKittrick, Kern County. California. The latter speci- 

 men shows slight peculiarities of color and cranium, but is much 

 nearer diaboli than any other form. In both places the zone is Upper 

 Sonoran; rather arid; hillside juniper association. 



Measurements. — Of type (adult female): total length, ISO mm.; 

 tail, 60; hind foot, 25; occipito-nasal length of cranium. 32.9; zygo- 

 matic width, 22.0; mastoid width, 17.IC height of braincase at bullae. 

 11.6; length of nasals. 10.3. Total length of six adults: ISO to 19?!. 

 average 189. 



Comparisons. — From Thomomys bottai h<ill<i< t Eydoux and Ger- 

 vais), of the San Francisco Bay region, the new form differs in very 

 much smaller size, less blackish, more reddish, coloration, relatively 

 smaller feet, .smaller teeth, and weaker rostrum. From topotypes of 

 T. annularis annularis Merriam. diaboli differs in much smaller size, 

 relatively smaller feet and ears, slightly darker and browner colora- 

 tion, much weaker rostrum, narrower incisors and less angular skull. 

 From T. leucodon navus Merriam, of the Sacramento Valley, diaboli 

 differs in slightly darker coloration, smaller size, much smaller molar 

 teeth, smaller auditory bullae, much shorter nasals and narrower 

 rostrum. From T. nigricans nigricans Rhoads, of the coast ranges of 

 San Diego County. <liah<ili differs in slightly paler coloration, and 

 notably in cranial characters: the nasals are much shorter, the incisors 

 project far more, and the braincase is broader and more inflated 



