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Our birds which build protected nests, or which are able to protect 

 their nests are not migratory birds as a rule. I know of but one clear 

 exception, the sapsucker. Our birds which build unsafe nests or which can- 

 not protect them are migratory birds as a rule. I know of no exception that 

 is clear. The Phoebe arrives when its food is scarce, and it leaves a land of 

 plenty, a land of insects ; food cannot be the attraction. That climate is 

 not the compelling cause is shown by the fact that many birds arrive when 

 the climate is very severe ; it even kills thousands of them sometimes. 



That birds are indigenous in the north ; that they are migrating in 

 the fall instead of the spring; that in the spring they are just going to 

 their preglacial home ; and that nostalgia is the real cause requires us to 

 believe that birds have a way of preserving a record of their lost Atlantis 

 that we do not possess, and may be dismissed as wholly psychological. 



The salmon goes a thousand miles up the Columbia to spawn ; the eel 

 question has at last been solved ; it goes to the deep sea to spawn. Sea- 

 birds go to isolated rocks for the same purpose. It is the conclusion of 

 this paper — there being no shred of evidence against it, and many weighty 

 reasons for it — that our migratory birds go north for safety in nesting. 



