122 THE COMMON CUCKOO. 



Winchat : but of these it has been observed, that she shows the greatest 



partiality to toe nest of the Hedge-Sparrow. 



We are indebted to the observations of Dr. Jenner, for the following 

 account of the habits and economy of this singular bird, in the dis- 

 posal of its egg. He states that, during the time the Hedge- Sparrow 

 xs laying her eggs, which generally occupies four or five days, the 

 Cuckoo contrives to deposit her egg among the rest, leaving the future 

 care of it entirely to the Ued.yre-Sparrow. This intrusion often occa- 

 sions some disorder ; for the old Hedge- Sparrow, at intervals, while she 

 is sitting, not only throws out some of her own eggs, but sometimes 

 injures them in such a way, that they become addle, so that it fre- 

 quently happens, that not more that two or three of the parent- bird 'a 

 eggs are hatched : but, what is very remarkable, it has never been 

 observed that she has either thrown out or injured the egg of the 

 Cuckoo. When the Hedge-Sparrow has set her usual time, and has 

 disengaged the young Cuckoo and some of her own offspring from the 

 shell, her own young-ones, and any of her eggs that remain unhatehed, 

 are soon turned out: the young Cuckoo then remains in full posses- 

 sion of the nest, and is the sole object of the future care of the foster- 

 parant. The young birds are not previously killed, nor are the eggs 

 demolished ; but they are left to perish together, either entangled in 

 the bush that contains the nest, or lying on the ground beneath it. 

 On the 18th of June, 1787, Dr. Jenner examined a nest of a Hede^e- 

 Sparrow, which then contained a Cuckoo r s and three Hedge-Sparrow's 

 eggs. On inspecting it the day following, the bird had hatched : but 

 the nest then contained only a young Cuckoo and one young Hedge- 

 Sparrow. The nest was placed so near the extremity of a hedge, that 

 he could distinctly see what was going forward in it ; and, to his great 

 astonishment, he saw the young Cuckoo, though so lately hatched, in 

 the act of turning out the young Hedge-Sparrow. The mode of accom- 

 plishing this was curious ; the little animal, with the assistance of its 

 rump and wings, contrived to get the bird upon its back, and, making 

 a lodgment for its burden by elevating its elbows, climbed backward 

 with it up the side of the nest, till it reached the top; where, resting 

 for a moment, it threw off its load with a jerk, and quite disengaged 

 it from the nest. After remaining a short time in this situation, and 

 feeling about with the extremities of its wings, as if to be convinced 

 that the business was properly executed, it dropped into the nest 

 again. Dr. Jenner made several experiments in different nests, by 

 repeatedly putting in an egg to the young Cuckoo; but this he always 

 found to be disposed of in the same mariner. It is very remarkable, 

 that nature seems to have provided for the singular disposition of the 

 Cuckoo, in its formation at this period ; for, different from other newly- 

 batched birds, its back, from the scapulae downward, is very broad, 

 with a considerable depression in the middle, which seems intended fo? 

 the express purpose of giving a more secure lodgment to the egg of 

 the Hedge-Sparrow or its youn^-one, while the young Cuckoo is em- 

 ployed in removing either of them from the nest. When it is about 

 twelve days old, this cavity is quite filled up, the back assumes the 

 shape of that of nestling birds in general, and at that time the dispo 



