224 THE PHILOSOPHY OF BIRDS’ NESTS. 
sparrows, and many other kinds fight furiously, and 
the conqueror of course has the choice of a mate. 
Mr. Spruce’s view is at least as probable as the con- 
trary one (that young birds, as a rule, pair together), | 
and it is to some extent supported by the celebrated 
American observer, Wilson, who strongly insists on 
the variety in the nests of birds of the same species, 
some being so much better finished than others; and 
he believes that the less perfect nests are built by the 
younger, the more perfect by the older, birds. 
At all events, till the crucial experiment is made, 
and a pair of birds raised from the egg without 
ever seeing a nest are shown to be capable of making 
one exactly of the parental type, I do not think we 
are justified in calling in the aid cf an unknown and 
mysterious faculty to do that which is so strictly 
analogous to the house-building of savage man. 
Again, we always assume that because a nest ap- 
pears to us delicately and artfully built, that it there- 
fore requires much special knowledge and acquired 
skill (or their substitute, instinct) in the bird who 
builds it. We forget that it is formed twig by twig 
and fibre by fibre, rudely enough at first, but crevices 
and irregularities, which must seem huge gaps and 
chasms in the eyes of the little builders, are filled up 
by twigs and stalks pushed in by slender beak and 
active foot, and that the wool, feathers, or horsehair 
are laid thread by thread, so that the result seems a 
marvel of ingenuity to us, just as would the rudest 
Iinand hut to a native of Brobdignag. 
