THE LIVING WORLD. 
307 
This power has probably been gradually acquired by the cuckoo , so as to give the 
female time to find a suitable nest in which to deposit each egg. It is possible 
that this singular habit of the cuckoo has arisen from its extraordinary voracity. 
The sexual instincts of the male cuckoo appear to be entirely subordinate to 
his greed for food. He jealously guards his feeding grounds, and is prepared to 
do battle with any other male that 
invades them, but he seems to be a 
stranger to sexual jealousy. He is 
said to be so absorbed in his gluttony 
that he neglects the females, who are 
obliged to wander in search of birds 
of the opposite sex, and appear to 
have some difficult}' in obtaining the 
fertilization of their ovaries. The 
extreme voracity of the young bird 
is an additional reason why the care 
of the five nestlings should be en¬ 
trusted to as many pairs of birds. 
“ In its choice of a foster-parent 
for its offspring, it exercises more 
discrimination than might be sup¬ 
posed from the long lists which 
have been published of birds in whose 
nests its eggs have been found. An 
insectivorous bird is generally wrinkled horned toucan /tote), 
■chosen, and preference is given to 
such as build open nests. Sometimes the cuckoo is unable to find the nest of 
a suitable bird, and is obliged to deposit its egg in the nest of a granivorous 
bird, such as the various species of 
finches, buntings, etc., and occasion¬ 
ally in the nests of jays, or even 
owls.” 
Different varieties lay eggs of 
different color, but they do not pos¬ 
sess the power of determining the 
color in order to imitate those of 
other birds, as some suppose. The 
natural food of the cuckoo is cater¬ 
pillars, especially those of the largest 
and most repugnant aspect, and 
also bumble-bees, of which it con¬ 
sumes great numbers. 
The mode by which the cuckoo 
contrives to deposit her eggs in the nest of sundry birds was extremely dubious, 
until a key was found to the problem by a chance discovery made by Le Var¬ 
iant. He had shot a female cuckoo , and on opening its mouth in order to stuff 
it with tow, he found an egg lodged very snugly within the throat. 
When hatched, the proceedings of the young ctickoo are very strange. As 
in process of time it would be a comparatively large bird, the nest would soon 
BEARDED CUCKOO (BuCCO flavigulci). 
