Young Cuckoo's Dress. 87 



" On skinning it (the cuckoo) I found its crop was 

 full of a mash of eggshells. I carefully examined this 

 mash and succeeded in separating the broken shells 

 (held together partly by the inside skin) of at least 

 seven eggs, two of which were robins, and the rest 

 either hedge sparrows' or thrushes', or some bluish 

 eggs." 



And Mr. Gurney avows himself a believer in occa- 

 sional egg-eating cuckoos. 



The great spotted cuckoos also eat eggs, as shells 

 have over and over again been found in their stomach.* 



Thus we reach some definite results. The cuckoo 

 destroys some of the eggs of the birds in whose nests it 

 places its own — sometimes it sucks them in the nest, 

 and carries out the shell in its beak : sometimes it 

 eats part of the shell and carries out the rest ; some- 

 times it eats the egg absolutely, shell and all. 



Another point : It would perhaps be rather strange 

 to the foster-birds if the young cuckoo had anything 

 like his true cuckoo feathers at first, which would be 

 something very different in aspect from that of their 

 own true progeny. But the young cuckoo does not 

 get his true feathers till before migration ; and so 

 long as he remains in the foster-parents' nest or under 

 their protection, his feathers are dull and dark, almost 

 black — another very peculiar point about the bird. 



And these distinguishing marks in plumage main- 

 tain themselves, though not to the same extent, en- 

 tirely through the first season. Lord Lilford wrote : 



" The difference of plumage between adults and 

 birds of the year is so singular and noticeable that 

 more than one writer on ornithology has treated of 



*Ibis, 1862, p. 358. 



