TKAYELS OF THE BIKDS. 



I. 

 Long before it became the f asMon for hu- 

 man city dwellers to '' go away for the sum- 

 mer " our little brothers and sisters of the air, 

 the birds, formed the habit of summering in 

 the cool North and wintering in the sunny 

 South. Many birds are great travelers. There 

 are species that spend the winter in the West 

 Indies, Central America, and even South 

 America, and the summer in Greenland and 

 Alaska. Some of these voyagers are tiny 

 birds, not more than three inches in length, 

 like the blue-gray gnat-catcher and the black- 

 throated blue warbler — gay little blossoms 

 with wings and beaks. It is simply wonderful 

 to think of the immense distances they traverse 

 in their semi-annual journeys, sweeping over 

 mountains, valleys, plains, and large bodies of 

 water, stopping at intervals to rest and recruit 

 their strength, and then resuming their airy 

 pilgrimage. Genuine "globe trotters" some of 

 them are. 



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