156 



CALIFORNIA ACADEMY OF SCIENCES. 



Length of incisive foramen, 8.5 mm. 



Length of rostrum from front of zygoma, 10.5 mm. 



Height of rostrum in front of zygoma, 8. mm. 



Length of base of upper molar series, 8.5 mm. 



Distance between posterior molars, 4.5 mm. 

 In No. 1207, a specimen of IV. mexicana* from the 

 Huachuca Mountains, Arizona, in which the basilar 

 length is 1^6 mm., the measurements agree very exactly 

 with the above, except in the longer nasals (18.5 mm.), 

 the longer rostrum (11 mm.), the longer incisive foramen 

 (10.5 mm.), and the distance separating latter from in- 

 cisors (3 mm.). 



The type specimen is adult, with the crowns of the 

 molars ground down almost to the base of the plications. 

 Six specimens, besides the type, are in the University 

 Museum, two from the same locality as the t3^pe, Bear 

 Valley, San Benito Count}^ and four collected by W. W. 

 Price, on Mt. Hamilton, Santa Clara Count}^, November 

 21 and 22, 1892. It is believed that all the specimens 

 thus far obtained were living among rocks. 

 LIST OF SPECIMENS. 



*The species here called Neotoma tiiexicana is represented in the museum of 

 the University by numerous specimens from the Huachuca Mountains, Arizona, 

 collected by the writer during the summer of 1893. No comparison has been 

 possible with N. mexicana from the typical locality, or with A'. pijietonini Mer- 

 riam, from the San Francisco Mountains. 



