CHAPTER XXV 



THE ENGLISH SPARROW: A STUDY OF BIRDS AND 

 MIGRATIONS 



IV'IosT animals, unlike most plants, are free to travel about in 

 search of food and mates. Thus everj^ morning in winter the 

 crows can be seen fl}'ing from their rookery in the forest to 

 distant fields where some grain still remains. At low tide 

 along the seashore many of them come to pick up clams. At 

 night they all fly back again to their rookery. When a famil}^ 

 has been raised, the j'oung move awaj^ from their birthplace 

 to seek feeding-grounds, mates, and homes of their own. 

 Usually this dispersal is so gradual that it is not observed ; 

 but in certain manmials the j'oung of a season may swarm 

 from their native home and traverse the country Hke an army. 

 This is the case with the widely known lemmings of Scandi- 

 navia. The importance of their march has been much exag- 

 gerated, for the migration has been noticed only a few times. 

 The numbers involved in these migrations, liowever, were 

 great. The lemmings travelled far ; some did not stop even 

 when they reached the sea, but plunged into it and were 

 drowned. Their Ijehavior well illustrates the blindness of the 

 impulse that drives them from home. 



Even man migrates when his native country' becomes over- 

 crowded and there are attractive prospects in other lands. 

 History records the migrations in ancient times of men from 

 central Asia into Europe, and one may witness any day at the 



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