3 22 



ELEMENTARY ZOOLOGY. 



the breast-bone is strong and wide, and still other bones 

 help to give a firm yet light framework suitable for the 

 attachment of the muscles of flight. The neck, on the 

 contrary, is slender and flexible. One of the most re- 



FIG. 130. A right 



iteral view of the skull of the American flamingo (Phcenicopter 

 ruber). Photo by Shufeldt. 



Questions on the Figure. Distinguish upper and lower jaws, 

 comparing them as to massiveness. Is this the usual condition in 

 birds? How much of the skull is occupied by the brain ? To what 

 habits of the flamingo is the form of the beak an adaptation? 

 Compare this figure with Figs. 108 and 122. 



markable bones in the flying birds is the breast-bone. It 

 is large and has a keel, extending vertically from it, to 

 which the heavy muscles of flight are attached. The 

 flat breast-bone does not present enough surface for this 

 purpose. There is a close correlation between the length 



