Key to the Rodentia
           
 
 Ear usually less than 22 mm; tail greater than length of head and body; auditory bullae average, not greatly inflated
(Fig. 59a)
   
 Ear usually more than 22 mm; tail less than length of head and body; auditory bullae large and inflated (Fig. 59b)
 
           
Artiodactyla
 - 
Carnivora
 - 
Chiroptera
 - 
Didelphimorphia
 - 
Insectivora
 - 
Lagomorpha
 - 
Rodentia
 - 
Xenarthra
Scientific Names - Common Names