Observations on the Cuckoo. 331 



hole under the eave of a cottage. This is mentioned, in the 

 last edition of Montagu, as being " rather a singular place 

 for a wagtail to build in ; " but I have known several wagtails' 

 nests in similar situations. Moreover, it seems Le Vaillant 

 found the egg of at least one species of African cuckoo, more 

 than once, in nests of small birds having a domed construc- 

 tion. It is obvious, therefore, that, in these cases (if correct), 

 it could never have been introduced in the ordinary manner; 

 still, we are very much in want of a mm and well-authenticated 

 instance of the occurrence of the European cuckoo's egg in a 

 situation where it would have been decidedly and totally im- 

 possible for the bird to have laid it. In all the cases which 

 have fallen under my observation, and in all that I have ever 

 heard of, from direct observers (and these amount to a very 

 considerable number), the nest was invariably so situate that 

 the cuckoo could have laid its egg into it. 



Besides, there is another consideration, which does not 

 appear to have occurred to those who have written on the 

 subject. How, in a domed nest, is the young cuckoo to get 

 rid of any companion which it may happen to have ? From 

 this single circumstance alone, I feel justified in doubting, at 

 least till farther proof can be adduced, the assertion of Mont- 

 beillard concerning the European cuckoo : it is possible he 

 was misinformed ; or the egg might have been introduced 

 into the wren's nest surreptitiously, by other and very differ- 

 ent agency from that of the cuckoo. 



Female cuckoos may not unfrequently be seen prowling 

 about, as if hunting for birds' nests. These, it is possible, 

 may always have an egg which they want to dispose of. It 

 would therefore, perhaps, be worth while to shoot a few of 

 them while thus engaged ; and, if they should then happen to 

 have an egg just ready to be deposited, to observe whether it 

 is ever carried in the mouth. I must confess, however, that 

 I do not myself believe that it is ever so carried. 



Those who are of the opinion of Montagu, that the female 

 cuckoo is endowed with the anomalous and extraordinary 

 power of retaining her egg, until, in consequence, it is some- 

 times quickened and partly advanced before it is laid, do not 

 appear to have duly considered the important fact, that the 

 cuckoo never places her egg in the nest of a bird which has 

 begun to sit (how could she ?) ; and that unless she were, in 

 this case, to do so, it would most inevitably perish. Of course, 

 every one must know that, after the vital action within an egg 

 has once commenced, a very short suspension of the necessary 

 heat is sufficient to destroy the embryo. No instance, how- 

 ever, that I am aware of, has ever yet been recorded of the 

 discovery of an addled cuckoo's egg. 



