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Peacock : The Cuckoo — A Study. 



creeping along- a branch like a Parrot for a long- distance at 

 a time, without using- its wing-s, its zygodactyle feet, with two 

 toes behind and two in front, being admirably adapted for the 

 purpose. If a nest with fresh laid eggs is securely placed in 

 a natural and suitable position a bird will sometimes lay her 

 egg in it. Occasionally two Cuckoo's eggs are found in one 

 nest, but they are generally supposed to be the deposits of 

 different birds. We do not yet know how many eggs the Cuckoo 

 lays in a season ; and the period of time that elapses between 

 the depositing of each egg is equally a matter of uncertainty. 



The small size of the Cuckoo's egg is also very remarkable. 

 In the words of the late G. T. Romanes, who studied this bird 

 carefully :- — 'The egg of the Cuckoo is not larger than that of 

 the Skylark, although an adult Cuckoo is four times the size 

 of a full grown Skylark.' In another place he also adds : — 

 i The small size of the egg is a real case of adaption — in order 

 to deceive the small birds in whose nest it is laid — we may infer 

 from the fact of the non-parasitic American Cuckoo (Coccyzus 

 americanns) laying full-sized eggs.' To this I reply it may be 

 so, but there is a much simpler explanation. This learned 

 author seems to have overlooked the fact that in almost every 

 case the European Cuckoo carries her egg in her bill, and those 

 which had small eggs would more easily achieve their object, 

 and hence by the theory of evolution the elimination of the 

 larger egg-producers would follow. In considering, this point 

 full}-, the wide gape of the Cuckoo should not be forgotten. 

 Compare that of the Night Jar and its food. Another note- 

 worthy point is the uncertain shade and marking's of Cuckoo's 

 eggs. They are often approximately — mind you, I only say 

 appro xifnately — coloured and flecked like those of the birds in 

 w r hose nests they are found. This no doubt aids in more 

 thoroughly deceiving the foster-parents. But I must hasten to 

 add that this is not invariably the case ; and even the country 

 lad oi limited experience can distinguish the Cuckoo's egg at 

 a glance. In Lincolnshire the egg is invariably of the ' grey 

 type,' as it is called. I have never heard of the ' blue ' and ' red 

 types ' found elsewhere. The egg, as I have already said, takes 

 fourteen days to incubate, and the young Cuckoo is usually, but 

 by no means always, first hatched. When it comes from the 

 shell it is k perfectly naked, without a vestige of feather, or even 

 a hint of future feathers. Its eyes are not yet opened, and it 

 seems too weak to support the weight of its own head, though 

 its legs are well developed and muscular.' Then follows the 



Naturalist, 



