t)0O BIRDS. 



ing the future care of it entirely to the hedge-sparrow. This in- 

 trusion often occasions some discomposure ; for the old hedge- 

 sparrow at intervals, while she is sitting, not unfrequently throws 

 out some of her own eggs, and sometimes injures them in such a 

 way that they become addle ; so that it more frequently happens, 

 that only two or three hedge. sparrow's eggs are hatched with the 

 cuckoo's, than otherwise ; but whether this be the case or not, she 

 sits the same length of time as if no foreign egg had Jaeen intro- 

 duced, the cuckoo's egg requiring no longer incubation than her 

 own. However, I have never seen an instance where the hedge- 

 sparrow has either thrown out or injured the egg of the cuckoo. 

 When the hedge-sparrow has sat her usual time, and disengaged 

 the young cuckoo and some of her own offspring from the shell*, 

 her young ones, and any of her eggs that remain unhatched, are 

 soon turned out, the young cuckoo remaining possessor of the nest, 

 and sole object of her future care. The young birds are not pre- 

 viously killed, nor are the eggs demolished ; but all are left to 

 perish together, either entangled about the bush which contains 

 the nest, or lying on the ground under it. 



The early fate of the young hedge-sparrows is a circumstance 

 that has been noticed by others, but attributed to wrong causes. 

 A variety of conjectures have been formed upon it. Some have sup- 

 posed the parent cuckoo the author of their destruction ; while 

 others, as erroneously, have pronounced them smothered by the 

 disproportioned size of their fellow-nestling. Now the cuckoo's 

 egg being not much larger than the hedge-sparrow's, it necessa- 

 rily follows, that at first there can be no great difference in the 

 size of the birds just burst from the shell. Of the fallacy of the 

 former assertion also I was some years ago convinced, by having 

 found that many cuckoo's eggs were hatched in the nests of other 

 birds, after the old cuckoo had disappeared; and by seeing the 

 same fate then attend the nestling sparrows as during the appear- 

 ance of old cuckoos in this country. 



Having found that the old hedge-sparrow commonly throws out 

 some of her own eggs after her nest has received the cuckoo's, and 

 not knowing how she might treat her young ones, if the young 

 cuckoo was deprived of the power of dispossessing them of the 

 nest, I made the following experiment. July 9. A young cuckoo, 



* The young cuckoo is commonly hatched first. Orig. 



