424 



ZOOLOGY 



Before civilized man destroyed their haunts and persistently 

 hunted them with his improved weapons, these were among the 

 very successful wild birds. Most species are now really quite 

 scarce. The only hope of preserving them is by legal protection 

 at critical times or by domestication. 



Chief among the domesticated birds is the common fowl 

 which is descended probably from a species native to southern 



Fig. 223. 



Fig. 22:i. Belted Kingfisher {Ccyic alcyon alcyon, L.). About one-fourth natural size. By J. W. 



Folsom. 



Asia, Galhis ferrugineus (bankiva). By breeding and selection 

 almost innumerable varieties have been produced. The poul- 

 try and egg industry is one of the most important in the coun- 

 try, amounting to more than 700,000,000 dollars annually. In 

 1920, about two billion dozens of eggs (estimated) were 

 produced on the farms of this country. This is one of the great 

 and reliable sources of human food. Turkeys, guinea-fowl, and 

 pea-fowl contribute in less degree. 



The ColumhcB {doves) are in many respects similar to the 



