112 ENGLISH BIRD LIFE 



upper branches of a tree. As the summer advances, 

 the cry becomes ahiiost incessant, and is frequently 

 heard in the midst of the night. At this season, 

 the large, grey, hawk-like bird may be seen wing- 

 ing its way from tree to tree, often crying as it 

 flies. In June, the note loses its clear sonorous 

 quality, and, before the end of July is reached, it 

 usually ceases altogether. 



The female Cuckoos are less numerous than the 

 males, and they lead a more secluded life in the 

 deeps of the woodlands. 



The parasitic habit of the Cuckoo has been the 

 theme of countless dissertations. How it comes to 

 be devoid of the maternal instinct, which is one of 

 the most powerful motive forces in animated Nature ; 

 by what discriminating processes it selects nests 

 suitable for the foisting of its egg ; how the egg is 

 inserted in nesting recesses far too small to admit 

 of the entrance of the female bird; how and b_y 

 whom the legitimate eggs and nestlings are ejected 

 — all these form questions to which an endless 

 number of answers have been supplied, with their 

 corresponding refutations. 



The broad facts are now pretty well agreed upon, 

 althouo^h the initial mvsterv remains untouched. In 

 the first place, the parasitic habit is not peculiar to 

 our Cuckoo ; it is shared by others of its Old World 

 relatives, and in America, by birds not at all related 

 to it. Again, although the nests of insectivorous 

 birds, especially those of the Meadow-pipit, Hedge- 

 sparrow and Pied Wagtail, are usually chosen, this 

 is by no means invariably the case, Cuckoo's eggs 

 having been found in the nests of no less than 



