y
that, with her mother-instinct to guide her, she could always find one
at a few moments' notice. Some people, who are never so happy as when
making the wonders of Nature seem still more wonderful than they really
are, have declared that the cuckoo lays eggs to match those among which
she deposits them, or that, at any rate, she chooses the nests of birds
whose eggs approximately resemble her own. I should have liked to
believe this, but am unfortunately debarred by the memory of about forty
cuckoo's eggs that I took, seven-and-twenty summers ago, in the woods
round Dartford Heath. The majority of these were found in hedgesparrows'
nests, and the absolute dissimilarity between the great spotted egg of
the cuckoo and the little blue egg of its so-called dupe would have
impressed even a colour-blind animal. Occasionally, I believe, a blue
cuckoo's egg has been found, but such a freak could hardly be the result
of design. As a matter of fact, there is no need for any such elaborate
deception. Up to the moment of hatching, the little foster-parents have
in all probability no suspicion of the trick that has been played on
them. Birds do not take deliberate notice of the size or colour of
their own eggs. Kearton somewhere relates how he once induced a
blackbird to sit on the eggs of a thrush, and a lapwing on those of a
redshank. So, too, farmyard hens will hatch the eggs of ducks or game
birds and wild birds can even be persuaded to sit on eggs made of
painted wood. Why then, since they are so careless of appearances,
should the cuckoo go to all manner of trouble to match the eggs of
hedgesparrow, robin or warbler? The bird would not notice the
difference, and, even if she did, she would probably sit quite as close,
if only for the sake of the other eggs of her own laying. Once the ugly
nestling is hatched, there comes swift awakening. Yet there is no
thought of reprisal or desertion. It looks rather as if the little
foster-parents are hypnotised by the uncouth guest, for they see their
own young ones elbowed out of the home and continue, with unflagging
devotion, to minister to the insatiable appetite of the greedy little
murderer. A bird so imbued as the parasitic cuckoo with the _Wanderlust_
would make a very careless parent, and we must therefore perhaps revise
our unflattering estimate of its attitude and admit that it does the
best it can by its offspring in putting them out to nurse. This habit,
unique among British b