Key to the Rodentia
           
 
 Dorsal color olivaceous; entire underside grayish with white tips, sometimes a little pure white on throat; lips dusky; antero-internal reentrant angle on molar extending at least halfway across anterior loop (Fig. 51a)
   
 Dorsal color gray washed with buff, throat and breast clear white, belly hair gray basally; no dark lips; antero-internal reentrant angle on molar extending less than halfway across the anterior loop (Fig. 51b)
 
           
Artiodactyla
 - 
Carnivora
 - 
Chiroptera
 - 
Didelphimorphia
 - 
Insectivora
 - 
Lagomorpha
 - 
Rodentia
 - 
Xenarthra
Scientific Names - Common Names