CUCKOO. 601 



that had been hatched by a hedge-sparrow about four hours, was 

 eonfined in the nest in such a manner that it could not possibly 

 turn out the young hedge-sparrows which were hatched at the 

 same time, though it was almost incessantly making attempts to 

 effect it. The consequence was, the old birds fed the whole alike, 

 and appeared in every respect to pay the same attention to their 

 own young as to the young cuckoo, till the 13th, when the nest 

 was unfortunately plundered. 



The smallness of the cuckoo's egg, in proportion to the size of 

 the bird, is a circumstance that hitherto I believe has escaped the 

 notice of the ornithologist. So great is the disproportion, that it 

 is in general smaller than that of the house-sparrow ; whereas the 

 difference in the size of the birds is nearly five to one. I have used 

 the term in general, because eggs produced at different times by 

 the same bird vary much in size. I found a cuckoo's egg so light that 

 it weighed only 43 grs., and one so heavy that it weighed 55 grs. 

 The colour of the cuckoo's egg is extremely variable. Some, both 

 in ground and penciling, very much resemble the house, sparrow's; 

 some are indistinctly covered with bran-coloured spots ; and others 

 are marked with lines of black, resembling in some measure the 

 eggs of the yellow-hammer. 



The circumstance of the young cuckoo's being destined by na- 

 ture to throw out the young hedge-sparrows, seems to account for 

 the parent-cuckoo's dropping her egg in the nests of birds so small 

 as those I have particularized. If she were to do this in the nest 

 of a bird which produced a large egg 9 and consequently a large 

 nestling, the young cuckoo would probably find an insurmount- 

 able difficulty in solely possessing the nest, as its exertion would 

 be unequal to the labour of turning out the young birds*. Be- 

 sides, though many of the larger birds might have fed the nestling 

 cuckoo very properly, had it been committed to their charge, yet 

 they could not have suffered their own young to have been sacri. 



* I have known an instance in which a hedge-sparrow sat on a cuckoo's egg 

 and one of her own. Her own egg was hatched five days before the cuckoo's, 

 when the young hedge-sparrow had gained such a superiority in size, that the 

 young cuckoo had not power sufficient to lift it out of the nest till it was two 

 days old, by which time it was grown very considerably. This egg was pro- 

 bably laid by the cuckoo several days after the hedge-sparrow had begun to 

 sit ; and even in this case it appears that its presence had created the disurb- 

 ance before alluded to, as all the hedge-sparrow's eggs were gone except one. 

 Orig. 



