59$ Bulletin American Museum of Natural History. [Vol. XIX, 



In addition to the Durango series I find in the Museum col- 

 lection a single specimen from Guadalupe y Calvo, Sierra 

 Madre, State of Chihuahua, collected in 1893 by Dr. Lumholtz. 



None of the many specimens from southern Arizona (White 

 Mts., Chiricahua Mts., Fort Lowell, Fairbank, etc.), nor from 

 Colonia Garcia (in the Sierra Madre of Chihuahua), shows any 

 marked tendency toward the present form, which, doubtless, 

 will be found to occur over a considerable area in Sonora and 

 southern Chihuahua, as well as in Durango. 



5. Mus musculus Linn. 



Six specimens: Rosario, i, Jan. 25; San Gabriel, 2, Feb. 18; 

 La Boquilla, 2, Feb. 16; Rancho Santuario, i, March 2. 



6. Mus rattus Linn. 

 Two specimens, Rio del Bocas, Feb. 8. 



7. Mus alexandrinus Geoff roy. 

 One specimen, Mt. San Gabriel, Jan. 8. 



8. Onychomys torridus (Coues}. 



Four specimens : Rosario, i, Jan. 24; Villa Ocampo, i, Feb. 

 12; Rio Sestin, 2, April n and 21. They do not seem to 

 differ appreciably from specimens from southern Arizona. 



9. Peromyscus paulus, sp. nov. 



Type, No. 21165, $ ad., Rio Sestin, northwestern Durango, April 

 17; J. H. Batty. 



Smaller than either P. musculus or P. m. brunneus and different in 

 color. Upper parts gray brown suffused with pinkish buff; under 

 parts grayish white, the base of the hairs being plumbeous and the tips 

 whitish; in some specimens a faint buffy tinge on the belly. 



Measurements. Type, total length, 108; head and body, 62; tail 

 vertebrae, 44; hind foot, without claws, 13, with claws (from dry skin), 

 14; ear, from notch, 13, from crown (in dry skin), n. Seven addi- 

 tional males give practically the same measurements as the type; 6 

 old females are slightly larger, as follows: Total length, 112 (108-117) ; 

 tail vertebrae, 44.3 (38-48); hind foot, 13 (12-14); ear, 12 (11-13). 



