THE TRAVELS OF BIRDS 



both are subject to the same laws of nature. A 

 Pelican could not lay eggs, hatch them, and care 

 for young Pelicans throughout the year any more 

 than an apple tree could bear several crops of 

 apples in a year. To develop either eggs or 

 apples takes strength, and the continued use of 

 one's strength means that one becomes tired and 

 must rest. 



So when the crop of Pelicans, -or of apples, 

 is ripe, the parent Pelicans as well as the parent 

 apple trees, rest. The Pelicans shed their 

 feathers, and since they could not live without 

 them, get a new set at once. The apple tree 

 sheds its leaves and the new set comes later. 

 Then fall and winter follow, and in both bird 

 and tree the instinct of reproduction rests. The 

 return of warm weather sets the sap flowing in 

 the trees, the buds begin to swell, blossoms open, 

 leaves unfold, and, in due time, the fruit ripens. 



With most birds, also, the coming of spring, 



if it does not actually start the sap flowing, sets 



new forces in action. These are the reproductive 



forces. They produce not buds, blossoms, and 



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