CUCKOO 93 



finds amiable hosts, sometimes unwilling ones, and in most cases a partly willing, 

 partly unwilling reception for her egg. Moreover, it was rare for the eggs of the 

 same race of cuckoo to resemble the eggs of all of the birds that were induced to 

 hatch them, although such a resemblance existed in certain cases. Consequently 

 the cuckoo not only found birds that would not accept her egg without demur 

 (although they would not refuse it) when it was like their own, but also others 

 that willingly lent themselves for foster-parents, even when the egg was quite 

 different from their own. Thus the fact that many cuckoos' eggs resemble those of 

 other birds is explained by the circumstance that birds are naturally averse to 

 them ; while the fact that the egg is very often unlike the other eggs in the same 

 nest may be explained by the sudden change of habit of many birds, owing to 

 cultivation, and also by the different degree of sensitiveness of the species of birds to 

 which the cuckoo entrusts the care of her young. The circumstance that cuckoos' 

 eggs are frequently marked with the markings of those of other birds seems to 

 indicate that the habitats of different races of cuckoo whose eggs differ from one 

 another have also been changed, so that members of different races have come in 

 contact with each other, paired and produced females which in turn laid eggs 

 with the colouring a mixture of that peculiar to each. In many parts of the 

 Continent there are, however, districts where individual cuckoos are not easily 

 to be distinguished by their eggs ; a sm - e sign that in such districts more or 

 less pure-bred local varieties of the cuckoo are still to be met with. For 

 instance, during a period of seven years there were found in Pomerania only 

 cuckoos' eggs with the same type of markings, and these in large numbers. 

 In some countries, as Dessau and Finland, the cuckoo's egg is almost exactly like 

 that of the redstart, while in Lapland it resembles that of the brambling. 



In different districts the cuckoo chooses different nurses, such as the redbreast 

 in Cassel, Naumburg, and Altenkirchen ; the wren in Pomerania ; the marsh- 

 warbler, the reed-warbler, and the sedge-warbler, in the islands of the lower 

 Elbe and those of the lower Rhine, at Wesel on the middle Elbe, at the 

 junction of the Saale and the Elbe, and on the lower Theiss and Danube ; the pied 

 wagtail, the hedge-sparrow, and the pipits in England ; the tree-pipit in Pomerania, 

 the redstart in Steiermark, the blue-throat in Norway, the brambling in north 

 Finland, and the redstart in other pai-ts of that country. The resemblance of the 

 cuckoo's egg to the eggs of its foster-parents is a means of protection, besides which 

 it is provided with other means for other cases, amongst which one of the chief is 

 its proportionately small size. Another protective feature is the hardness of 

 the shell, which prevents the egg from being pecked to pieces by unwilling foster- 

 parents and from being broken by the cuckoo herself when carrying it in her 

 gullet or beak. In addition to these peculiarities of the egg, there are certain 

 instincts in the cuckoo which also serve for the preservation of the race. The hen 

 deposits, for instance, only one egg in each nest ; and the survival of the species 

 is dependent on the different hatching-times of the birds to which the egg is 

 entrusted. In the case of birds which breed twice a year the cuckoo seems to 

 deposit two series of eggs. When in search of a suitable nest, the female flies 

 almost noiselessly through low copses or reeds, across open spaces in the forest, 

 meadows, and fields, and if she find the owners close to one adapted for her 



