1895.] NATURAL SCIENCES OF PHILADELPHIA. 35 



the outer posterior corners, the latter coming far short of the nasal 

 prolongations of the premaxilluries. Upper and lower incisors un- 

 usually wide and strong, the upper inner sulcus scarcely noticeable 

 without a glass. Molar dentition likewise unusually massive. The 

 coronoid process of mandible is more erect than usually seen in the 

 genus and terminates in a sharp point. 



Measurements (of type in millimeters).— Total length, 228; tail 

 vertebrae, 74; hind foot, 29; arc of middle fore-claw, 11.5. Skull — 

 Total length, 39.7; basilar length, 34; greatest zygomatic width, 

 23.2; interorbital constriction, 7; length of nasals, 13; terminal 

 width of upper pair of incisors, 4.6. 



Three specimens of this gopher, taken at varying elevations of 

 from 5,000 to 7,000 feet in the San Bernardino Mountains by Mr. 

 Herron, form the basis of the foregoing description. 



Though somewhat affected by albinism, as stated in the description, 

 I have chosen the type as being the most typical of the three speci- 

 mens, the other two being less fully developed in cranial characters 

 and are in more worn pelage. The type may be considered repre- 

 sentative of the maximum development of the species, the others 

 averaging considerably less in body and cranial measurements. 

 This species may be compared to three described forms. From T. 

 toltecus it differs in a smaller body, longer tail, and much smaller 

 and more elongate skull, also in the darker upper and very much 

 darker lower body colors; from T. monticolus the San Bernardino 

 gopher differs radically in the small size and narrowness of the in- 

 terparietal, in the marked prolongation and acuteness of the fronto- 

 intermaxillary suture beyond the nasals, in its wide mastoid and 

 zygomatic development, and in the diminution of the inner ridges of 

 the faces of the upper incisors. Iu color, altivallis differs from 

 monticolus in a less marked degree, but in the same respects as 

 already described in its separation from toltecus. In some respects 

 altivallis resembles bottce from Nicasio, California. It may be dis- 

 tinguished therefrom by its more fulvous shade above, by the dark 

 dorsal stripe, black nose, and sooty under parts, and by the greater 

 size of manus and strength of fore claws. Cranially bottce is more 

 massive, with a slender rostrum and weaker dentition, narrower in- 

 terparietal and wide zygoma 1 . In altivallis there are no parietal 

 ridges which are so characteristic of bottw of same age. 



