68 h\fe History of Common Cuckoo. 



of a warbler or chiff-chaff — the eggs of it are so 

 differently coloured that the sombre cuckoo's egg lies 

 in striking contrast." '^• 



But, as I said already, in the British Museum, one 

 of the clutches has most distinctly a blue cuckoo's 

 egg beside the accentor's eggs, that of the cuckoo 

 being only noticeably larger ; and in another clutch 

 there a blue cuckoo's egg lies beside the live blue 

 eggs of the redstart, here, too, only a little larger than 

 them, but in tint exactly matched. It is clear that 

 the intention of a blue egg is to be laid with blue 

 eggs ; and if we could but definitely get at the causes 

 of the cuckoo's power so to place it, we should be 

 some steps nearer to a true understanding of this bird. 



Many instances we have now of blue cuckoos' eggs 

 in nests of hedge-sparrow. Professor Newton writes : 



" One was recorded in Zoologist, 1873 (p. 3526), on 

 Mr. Brine's authority, and a few others have since 

 been recorded." + We have heard of several quite 

 recently and ourselves found two in North - East 

 Essex the season before last and one last year so 

 ahke in tint that only a slight excess in size betrayed 

 them : and there is Mr. Read's specimen exhibited in 

 Mr. Bid well's exhibition. 



* Handbook, ii, p. 28. 



\ Dictionary of Birds , i, p. I2i. [Now, this is not correct : Mr. 

 Brine, as we have seen, declared the finding of such several 

 times, and in the specific case referred to there were two cuckoos' 

 eggs — one as dark blue as the hedge-sparrow's, the other lighter. 

 If Mr. Brine was to be believed about one, he should have been 

 believed about the rest, or else very distinct reasons given why 

 he was believed about the one and not about the others Dis- 

 crimination is good ; but picking and choosing with birds are 

 sometimes not so good.] 



