RECENT LAND MAMMALS OF WESTERN NORTH AMERICA 



149 



Table I. — (Continued) 



Thomomys 



Geomys 



Cratogeomys 



Liomys 



Perognathus 



Dipodomys 



Microdipodops 



Castor 



Onychomys 



Reithrodontomys 



Baiomys 



Peromyscus 



Oryzomys 



Sigmodon 



Neotoma 



Synaptomys 



Lemmiis 



Dicrostonyx 



Phenacomys 



Clethrionomys 



Microtus 



Lagurus 



Pitymys 



Neofiber 



Ondatra 



Aplodontia 



Zapus 



Napaeozapus 



Erethizon 



Ochotona 



Lepus 



Sylvilagus 



Pecari 



Cervus 



Odocoileus 



Alces 



Rangifer 



Antilocapra 



Bison 



Ovibos 



Ovis 



Oreamnos 



