CHAPTER X 



Pigeons 

 ORDER— COLUMB^ 



PIGEONS are now generally believed to be very 

 near relations of the Plover tribe, little as these 

 two groups appear to have in common, judged 

 by external characters alone. When, however, we 

 compare them anatomically, we gain true insight into 

 their relationships. 



Pigeons are, for the roost part, short-legged, ar- 

 boreal birds. Certain forms, however, such as the 

 Crowned Pigeons and a few others, have taken to liv- 

 ing on the ground, and in these the legs are much 

 longer than in the tree-living species. 



Two white eggs are laid in a season and the parents 

 relieve each other in the task of incubating. The 

 young are hatched naked and are for a long time help- 

 less. Pigeons are remarkable from the fact that the 

 inner walls of the crop, which is of great size, are richly 

 provided with blood-vessels which during the breeding 

 season secrete what is known as "Pigeon's milk," and 

 on this the young are fed, the parent thrusting its bill 

 into the mouth of the young and regurgitating this 

 substance. 



The Pigeon family is a very large one, consisting of 



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