VERTEBRATA 



263 



appendage to the head. Their principal food is grain. 

 The order comprises the common Fowl, Turkey, Par- 

 tridge, Grouse, Pheasant, Ptarmigan, and Pea-fowl. 



The preceding orders form a legion called Autopliagi, 

 since immediately on being hatched they can run about 

 and look after themselves. The remaining orders form 

 the legion Heterophagi, in which the young are depend- 

 ent upon their mother for nourishment for some time 

 after birth. 



Order 5. Columbce, or Pigeons. These differ from the 

 Scratchers in possessing powerful wings. They have 

 slender legs, with toes ununited, and the hind toe on a 





P'iG. 159. Wood-Pigeun. 



level with the rest. Pigeons, Doves, (Fig. 159,) and the 

 extinct Dodo are found in this order. 



Pigeons exhibit in a great degree the mutability of 

 races or varieties ; all the vast number of Pigeons, 



