HABITS OF CUCKOO 211 



it was barely possible that she could make her way, 

 or, again, into a nest which, as in the case of the 

 garden-warbler or the blackcap, is so slender and so 

 slenderly supported, that it could not bear her 

 weight even for a moment ? Does she, when there 

 is room for such a feat of aerial skill, hover, for a 

 brief space, over the nest, as the swallow will 

 sometimes hover, for a moment, over your head, 

 when you are near its nest, or as a kingfisher will 

 sometimes hover over the stream, before he dives 

 for the minnow, and deftly drop her egg into it, or 

 does she lay it elsewhere, and carry it delicately to 

 its destined home in her bill or claw? Does the 

 unfortunate foster-mother notice the unauthorised 

 introduction of an egg into her nest, often so 

 unlike in colour to her own ? Does she realise, 

 when at last she hatches her eggs, that all her own 

 offspring must needs perish, in order that the young 

 intruder may survive ? Why does she show no 

 pity for her own callow young, so ruthlessly thrown 

 out, one after the other, from their proper home 

 and left to perish below ? Whence comes the self- 

 forgetting devotion that leads the foster-parents 

 to spend and to exhaust all their energies in feeding 

 their overgrown foster-child, which soon becomes 

 twice as big as themselves ; and whence comes to 



