392 GENERAL SCIENCE 



eggs instead of this being done by the female sparrow. 

 If a nest is torn down in the middle of the summer, 

 you will find in it eggs and birds of various ages up 

 to those that are mature and ready to fly out. This 

 method of reproduction makes the English sparrow very 

 prolific and it becomes a menace to the welfare of all other 

 birds. Many states offer a bounty of two cents a head for 

 English sparrows in order to bring about their destruction. 



The crow, a large black bird, migrates, going south in 

 autumn and coming back in the spring. Crows are very 

 destructive to germinating corn in the farmers' fields in 

 the spring. Their diet ' consists mostly of grain, but 

 occasionally they take up the habit of hawks, eating small 

 birds and even young poultry grown by the farmers. 

 They also rob the nests of other birds. They gather in 

 great flocks during their migrating season and stop 

 occasionally on the migrating tours in the various grain 

 fields to gather their evening meals. 



The blackbird is about half the size of the crow. They 

 also migrate, traveling in great flocks, living largely upon 

 the farmers' productions. About two-thirds of their diet, 

 however, is composed of insects and bugs of various 

 kinds. 



The birds most valuable to the American farmer are 

 the robin, bluebird, martin, and various other kinds of 

 songbirds. Their principal value is in destroying or 

 consuming great numbers of insects which are harmful to 

 the crops. 



The domesticated birds which can be found on any 

 farm originated from various types of wild birds. The 

 chickens have originated from a wild bird of Asia and 

 the geese and ducks from various types of the wild kind. 

 Many of the birds which have given origin to domesticated 



