Birds by Land and Sea 



development by the narrow walls of an unnaturally 

 small egg ? 



That the egg, being small, should be deposited 

 almost always in the nests of small birds is probably 

 due to the cuckoo's fear of meddling with the nests 

 of larger birds, rather than to a perception of fitness ; 

 for the egg has occasionally been found in the nests 

 of larger birds, the eggs of which exceed that of the 

 cuckoo in size as markedly as the latter exceeds 

 those of some of the smaller birds in the nests of 

 which it is at times deposited. Is it, again, to the 

 cramped feeling of the large young bird in a small 

 nest, coupled with a sudden access of expansive 

 vigour, which may well accompany its release from 

 its unnaturally close confinement in an under-sized 

 egg, that we must ascribe the origination of the 

 ejecting impulse ? Would it have arisen if the 

 cuckoo had habitually placed its egg in the roomier 

 nests of larger birds ? 



I am not disposed to regard the depositing of 

 one egg only in a foster nest as an act of foresight 

 on the part of the parent cuckoo. The bird has no 

 nest, and has ceased to feel the attraction which 

 makes of the nest the central point of interest for 

 birds of a more domestic habit. It is a wanderer, 

 and upon occasion seeks the first suitable place where 

 it may deposit its egg in obedience to the last 

 prompting of an almost extinct maternal instinct. 



I am as little disposed to regard as an act of 

 foresight the destruction by the parent cuckoo of 



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