184 
FRANCIS H. HERRICK 
by Baldamus and others, as to the way in which fate overtakes 
the eggs and young of the nurse. ''The female cuckoo removes and 
hides the eggs of the nurse, after the young parasite is hatched, 
and has been adopted, and in doing this it is attended by the male 
who keeps in the vicinity of the nest." (Baldamus and others.) 
^'In nests which it cannot readily reach, the young of the nurse 
sometimes grow up, but are often suffocated or starved out by 
the young cuckoo, and are later removed by their own parents 
for the sake of cleanliness." (Baldamus.) 
It would thus appear that the evicting instinct of young cuckoos 
is neither perfect nor universal, and that the young of the foster- 
parents are often treated precisely as in the case of our cowbird. 
If true that the adult cuckoo ever removes the unbroken eggs 
of the nurse, when its young fails to do so, it is evident that this 
is not regularly done, but it would be useless to speculate on the 
significance of such an extraordinary act, without more precise 
knowledge of the conditions under which it is supposed to 
occur. 
18. The European cuckoo is now generally absolved from the 
stigma of eating the eggs or the young of other birds. The eggs 
which have been found in the bill or oesophagus of a shot bird, are 
supposed to be either its own which it was carrying to some nest, 
or those of a nurse (see section 12) which it was in the act of 
removing. (Baldamus and others.) 
19. Adult cuckoos, when the opportunit}" offers, feed freely 
on hairy caterpillars, so universally rejected by other birds. They 
hav^e large, thin-walled stomachs, the mucous membranes of which 
are often 'furred' with the sharp, stiff hairs or setae of these 
insects. They also take a great variety of other insect prey, 
in the adult and larval state, a few berries, and incidentally a 
little sand and very small pebbles. 
20. The European cuckoo, coming from a smaller egg, is 
less advanced at birth than in the case of the American species. 
Incubation of the cuckoo's egg has been known to last two weeks 
(Weir: by titlark. May 23-June 6) ; the young are born not only 
blind, but according to most accounts, without any trace of 
