THE CUCKOOS AND THE OUTWITTED COW-BIRD 41 



fact well known to ornithologists that our own 

 American cuckoos, both the yellow -billed and 

 black - billed, although rudimentary nest -builders, 

 still retain the same exceptional interval in their 

 egg -laying as do their foreign namesake. The 

 eggs are laid from four days to a week apart, in- 

 stead of daily, as with most birds, their period of 

 perilous riidification on that haphazard apology of 

 a nest being thus possibly prolonged to six weeks. 

 Thus we find, in consequence, the anomalous spec- 

 tacle of the egg and full-grown chick, and perhaps 

 one or two fledglings of intermediate stages of 

 growth, scattered about at once, helter-skelter, in 

 the same nest. Only two years ago I discovered 

 such a nest not a hundred feet from my house, 

 containing one chick about two days old, another 

 almost full-fledged, while a fresh -broken egg lay 

 upon the ground beneath. Such a household 

 condition would seem rather demoralizing to the 

 cares of incubation, and doubtless the addled or 

 ousted egg is a frequent episode in our cuckoo's 

 experience. 



It is an interesting question which the contrast 

 of the American and European cuckoo thus pre- 

 sents. Is the American species a degenerate or 

 a progressive nest-builder ? Has she advanced in 

 process of evolution from a parasitical progenitor 



