LAND BIRDS 



293 



plump, and the plumage has a peculiar iridescence. Some 

 live on the ground, others in trees, and still others in open places. 



The turtle dove, or mourning dove, is one of our commonest species and 

 its plaintive cooing is quite familiar to all. It breeds throughout the 

 United States, and one often meets it in the country roads. It is one of the 

 farmer's useful, as well as beautiful, friends. Three stomachs, examined 

 at Washington, were found to contain 23,100 weed seeds. 



Darwin says our domestic pigeons originated from the blue-rock pigeon 

 (Colum'ba liv'ia). The nest of the pigeon is a flimsy one of twigs, on which 

 it lays two white eggs, from which hatch the naked, altricial " squabs." 



JtUTUMN . 



Fig. 239. Seasonal changes of color in ptarmigan (Lngo'pus mu'tus); 

 % natural size. (Romanes.) 



Both sexes incubate. The young are fed on " pigeon's milk," the parent 

 thrusting its bill into the mouth of the young and discharging therein 

 food which has been softened in its own crop. Chapman and Reed say 

 also that some species of pigeons nest in isolated pairs and other species in 

 large colonies. If you have ever watched a pigeon drink, you know that it 

 holds the bill in the water till it has finished drinking. The passenger 

 pigeon is a noted bird for sending messages. It was formerly very abun- 

 dant. In 1808 Wilson estimated one flock at over 2,000,000,000 pigeons. 

 They are now almost extinct, another result of the hunter and his gun. 



Allied to the pigeons was the extinct dodo of Madagascar. It was a 

 giant compared to our pigeons. Look up a picture of it 1 and see what a 

 strange looking bird it was. It could not fly. 



1 Evans, " Birds," p. 329. 



