42 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. XI. 



GROUP 2. Order UNGULATA. Hoofed Mammals. 



SECTION 1. Horns branched and solid (not hollow) and annually 

 shed. 



Family CERVID^E. 

 Deer, Moose, Caribou, etc., p. 58. 



SECTION 2. Horns simple (not branched), permanent (not annually 

 shed), and more or less hollow. 



Family BOVID^E. 

 American Bison or Buffalo, etc., p. 86. 



GROUP 3. Order GLIRES. Gnawing Mammals. Squirrels, Rab- 

 bits, Rats, Beavers, etc. 



Front teeth (incisors) large and chisel- 

 shaped and separated from the molars on 

 side of jaw by a wide gap; canine teeth ab- 

 sent; toes with nails or claws. 



Skull of a Rodent. 



