above the earth, the call notes coming incessantly out of the darkness. The 

 route of these flying hosts often carries them above cities, and one cannot be 

 insensible to the incongruity between his surroundings and the woodland scenes, 

 so vividly brought to mind by the lisping notes coming from the darkness over- 

 head. The subject of migration has not inspired our poets so often as might 

 be expected, but Longfellow, in his "Birds of Passage," gives us the following 

 wonderfully suggestive lines : 



But the night is fair, 



And everywhere 



A warm, soft vapor fills the air, 



And distant sounds seem near; 

 And above, in the light 

 Of the star-lit night, 

 Swift birds of passage wing their flight, 



Through the dewy atmosphere. 



I hear the beat 



Of their pinions fleet. 



As from the land of snow and sleet 



They seek a southern lea. 

 I hear the cry 

 Of their voices high, 

 Falling dreamily through the sky. 



But their forms I cannot see. 



Probably because insects constitute such an important part of their food, 

 warblers, as a rule, migrate early in fall and late in spring. It is true that in fall 

 many linger till frosts nip the vegetation; but insects are abroad even later than 

 this, and it is only necessary to watch these late migrants for a short time to 

 learn that their search for insects is being well rewarded. 



Only a few species come north early in spring, the great bulk of the warblers 

 evidently having been taught by bitter experience that in spring, at least, it is not 

 the early bird that finds most worms or finds them easiest. 



FLOCKING OF SMALL BIRDS 



Just why small birds, when migrating, congregate in large flocks and troop 

 through the woodlands has often been the subject of speculation. Juncos, several 

 species of sparrows, woodpeckers, nuthatches, chickadees, creepers, and, above 

 all, warblers, combine to swell the ranks of these migrating companies. As many 

 as a dozen or more species of warblers may often be seen in one flock, which, in 

 addition, may include 200 or 300 individuals, representing a number of families 

 whose tastes and habits in every-day life differ very widely. 



Yet here are these incongruous elements mingling together on terms of the 

 utmost friendliness. Since birds are sociable beings, except during the short 

 time when family cares prompt to jealous vigilance, sociability alone may be the 

 bond of union ; added, however, to the kindly feeling of companionship probably 



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