PARROTS, CUCKOOS, AND PLANTAIN-EATERS 495 



only after the bird had ascertained its colour. If this were true, surely we should find blue 

 cuckoos' eggs in hedge-sparrows' as well as redstarts' nests. But we don't ! Others have sought 

 to explain the existence of mimicking eggs to the influence of the food peculiar to the foster- 

 parent upon the germ of the young female cuckoo, which, through this channel, became 

 transmitted to all its descendants. To support this hypothesis it was necessary to throw over- 

 board the old individual variability explanation, and to adopt one that is certainly nearer the 

 truth to wit, that each cuckoo chooses the nest of that species in which itself was reared 

 as a depository, in turn, for its own egg, and only when such is not available will it select 

 some other species, and trust to luck for its adoption. This would certainly account for many 

 anomalies ; but as it seems that there are more eggs unlike than like those of the selected 

 foster-parents, it cannot be a perfect explanation. 



A third explanation takes that part of the second for granted which assumes that cuckoos 

 select nests of the species which served them as foster-parents, and explains the mimicry, 

 when this occurs, as due to the results of natural selection. 



Our interest, however, in the domestic economy of the common cuckoo is not to be 

 allowed to drop with the incubation of the egg. The perfidy of the parents seems to have 

 cast a sombre shadow over the cradle of the offspring, an evil spell destined to bear fruit with 

 terrible suddenness; for the young, before it is -many hours old, and while yet blind and 

 naked, perpetrates its first act of wrong-doing by committing murder ! There is no case here 

 of wilful or ignorant misrepresentation and slander, such as many of our feathered friends are 

 made to suffer at our hands no foolish prejudice such as has blasted the reputation of some 

 of our most guiltless and useful of bird-citizens. The witnesses of the crime of which we speak 

 are many and unimpeachable. The facts are as follows : 



The parent cuckoo deposits her egg in the nest of some other bird with those of the 

 owners thereof. All are hatched. In a few hours after the arrival of the young cuckoo the 

 foster-brothers and -sisters invariably disappear, and are not seldom found in the immediate 

 neighbourhood of the nest. That they must have been removed by force is certain ; but 

 this force cannot be attributed to the natural parents. The evidence of the first witnesses, 

 therefore, was worthy of all consideration ; and since their accounts have been frequently 



thua tj BiUi*gun\ 



PHEASANT-CUCKOO 



The hind toe terminates in a sfur-likc claw ; hence these cuckaot are knotvn as Lark-heeled Cuckoos 



