THE STRUCTURE AND ACTIVITIES OF BIRDS 359 



Growth of the Young (Figs. 235, 236 A, 2366). The young 

 hatch with a covering of down (precocial birds) or practically 

 naked (altricial birds). They devour large quantities of food, 

 principally insects, and grow rapidly. The feathers gradually 

 grow in, but are often different from those of the parents in 

 color. 



REFERENCES 



A Dictionary of Birds, by A. Newton and H. Gadow. Adam and Charles 



Black, London, England. 

 Key to North American Birds, by E. Coues. Estes and Lauriat, Boston, 



Mass. 

 Bird-Life, by F. M. Chapman. D. Appleton and Co., N. Y. City. 



