396 cucuLiD^. 



I have since repeated several times in different nests, and 

 have always found the young Cuckoo disposed to act in the 

 same manner. In climbing up the nest, it sometimes drops 

 its burden, and thus is foiled in its endeavours ; but, after a 

 little respite, the work is resumed, and goes on almost 

 incessantly till it is effected. It is wonderful to see the 

 extraordinary exertions of the young Cuckoo, when it is 

 two or three days old, if a bird be put into the nest with it 

 that is too weighty for it to lift out. In this state it seems 

 ever restless and uneasy. But this disposition for turning 

 out its companions begins to decline from the time it is two 

 or three till it is about twelve days old, when, as far as I 

 have hitherto seen, it ceases. Indeed, the disposition for 

 throwing out the eggs appears to cease a few days sooner ; for 

 I have frequently seen the young Cuckoo, after it had been 

 hatched nine or ten days, remove a nestling that had been 

 placed in the nest with it, when it suffered an egg, put there 

 at the same time, to remain unmolested. The singularity 

 of its shape is well adapted to these purposes ; for, different 

 from other newly-hatched birds, its back from the scapula 

 downwards is very broad, with a considerable depression in 

 the middle. This depression seems formed by nature for 

 the design of giving a more secure lodgement to the egg of 

 the Hedge-sparrow, or its young one, when the young 

 Cuckoo is employed in removing either of them from the 

 nest. When it is about twelve days old, this cavity is quite 

 filled up, and then the back assumes the shape of nestling 

 birds in general." 



This remarkable habit of the young Cuckow has been so 

 abundantly confirmed by the testimony of unimpeachable 

 eye-witnesses in many countries, and in England among 

 others by Montagu and Mr. Blackwall, whose names are a 

 sufficient guarantee for the accuracy of their observations, 

 that the unbelief in Jenner's statements, hinted or openly 

 expressed by some zoologists is hardly to be justified by the 

 most ardent supporter of absolute proof.* In 1872 a lady 



* It is painful to find Waterton one of tlie strongest impugners of Jenner's 

 worJ, and, without any warrant, declaring dogmatically in a letter to Ord 



