370 THE SONORAN REGION. [CHAP. 



Insectivora (cont.). 

 TALPID^E. 



Scalops. Enters Transition zone. 



Scapanus. Enters Canadian sub-region of Holarctic. 



Carnivora. 



PROCYONID^E. 



Bassariscus. Enters Transition and Central America. 

 Procyon. N. to S. America. 

 Nasua. Also South American. 



MUSTELID^E. 



Spilogale. Enters Transition and Central America. 



Conepatus. Texas to Patagonia. 



Mephitis. Extends into Canadian sub-region and 



Central America. 

 Taxidea. Enters Holarctic. 



Rodentia. 



Cynomys. Extends into Holarctic. 



MURID^E. 



Rhithrodontomys. 



Sitomys. The whole of America. 



Sigmodon. Southwards to Ecuador. 



Neotoma. Ranges into Holarctic. 



Neofiber. 

 GEOMYID^E. 



Geomys. Extends into Transition zone and Central 

 America. 



Thomomys. Ranges into Canadian sub-region. 



Dipodomys. 



Perodipus. 



Microdipodops. 



Perognathus. Ranges into Transition zone. 



Heteromys. 



Ungulata. 



A NTIL OCA PRIDJE. 



Antilocapra. Ranges into Canadian sub-region. 



