SO 6 BRITISH BIRDS. 
fometimes injures them in fuch a way that they 
become addle, fo that it frequently happens that 
not more than two or three of the parent bird’s 
eggs are hatched with that of the Cuckoo ; and 
what is very remarkable, it has never been obfer- 
ved that the Hedge- fparrow has either thrown out 
or injured the egg of the Cuckoo. When the 
Hedge-fparrow has fat her ufual time, and difen- 
gaged the young Cuckoo and fome of her own off- 
fpring from the fhell, her own young ones, and 
any of her eggs that remain un hatched, are foon 
turned out, the young Cuckoo remaining in full pof- 
feffion of the neft, and the foie object of the future 
care of her folter parent. The young birds are not 
previoufly killed, nor the eggs demolifhed, but all 
are left to periih together, either entangled in the 
bufh which contains the neft, or lying on the 
ground under it. Mr Jenner next proceeds to ac- 
count for this feemingly unnatural circumftance ; 
and as what he has advanced is the refult of his 
own repeated obfervations, we ftiall give it nearly 
in his own words. “ On the 18th June, 1787, 
Mr J. examined the neft of a Hedge-fparrow, which 
then contained a Cuckoo’s and three Hedge-fpar- 
row’s eggs. On infpe&ing it the day following, 
the bird had hatched, but the neft then contained 
only a young Cuckoo and one young Hedge-fpar- 
row. The neft was placed fo near the extremity 
of a hedge that he could diftin&ly fee what was 
going forward in it; and, to his great aftonilh- 
