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and as to our birds, the subject can never be 

 forever set at rest, seeing that the birds will not 

 obey the rules, and only laugh at notices to effect 

 that this field belongs to another species : No 

 trespassing. Unfortunately, birds are the arch- 

 trespassers of wild life. There is no barrier 

 that they cannot surmount if they choose to do 

 so ; no solid sheets of air, like plate-glass par- 

 titions, through which they cannot go. That 

 they do not overstep far more than they do is 

 to be wondered at, and that geographical distri- 

 bution is so much of a factor of our ornithology 

 is strange, seeing that some of our weaker- 

 winged birds travel north and south for an 

 enormous distance twice a year. That faunal 

 lines can be drawn where there are no mountain 

 ranges even to be crossed is a remarkable feature 

 of this subject as applied to my own neighbor- 

 hood. A man can walk from Maine to Florida ; 

 any bird can fly that distance. Some do so ; 

 why not all ? Perhaps, why do any ? We have 

 not yet solved the problem of migration, and 

 now the question rises, Has it varied since the 

 earlier records of the phenomenon ? We know 

 that some birds have left us that were once 



