BIRDS IN THE CALENDAR 



deliberate notice of the size or colour of their 

 own eggs. Kearton somewhere relates how 

 he once induced a blackbird to sit on the eggs 

 of a thrush, and a lapwing on those of a red- 

 shank. So, too, farmyard hens will hatch the 

 eggs of ducks or game-birds and wild birds 

 can even be persuaded to sit on eggs made of 

 painted wood. Why then, since they are so 

 careless of appearances, should the cuckoo 

 go to all manner of trouble to match the eggs 

 of hedgesparrow, robin or warbler ? The bird 

 would not notice the difference, and, even if 

 she did, she would probably sit quite as close, 

 if only for the sake of the other eggs of her 

 own laying. Once the ugly nestling is hatched, 

 there comes swift awakening. Yet there is 

 no thought of reprisal or desertion. It looks 

 rather as if the little foster-parents are hyp- 

 notised by the uncouth guest, for they see 

 their own young ones elbowed out of the home 

 and continue, with unflagging devotion, to 

 minister to the insatiable appetite of the 

 greedy little murderer. A bird so imbued as 

 the parasitic cuckoo with the Wanderlust 

 would make a very careless parent, and we 

 must therefore perhaps revise our unflattering 

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