ves have been so far
conquered by naturalised productions, that they have allowed foreigners
to take firm possession of the land. And as foreigners have thus
everywhere beaten some of the natives, we may safely conclude that the
natives might have been modified with advantage, so as to have better
resisted such intruders.

As man can produce and certainly has produced a great result by his
methodical and unconscious means of selection, what may not nature
effect? Man can act only on external and visible characters: nature
cares nothing for appearances, except in so far as they may be useful
to any being. She can act on every internal organ, on every shade of
constitutional difference, on the whole machinery of life. Man selects
only for his own good; Nature only for that of the being which she
tends. Every selected character is fully exercised by her; and the being
is placed under well-suited conditions of life. Man keeps the natives
of many climates in the same country; he seldom exercises each selected
character in some peculiar and fitting manner; he feeds a long and a
short beaked pigeon on the same food; he does not exercise a long-backed
or long-legged quadruped in any peculiar manner; he exposes sheep with
long and short wool to the same climate. He does not allow the most
vigorous males to struggle for the females. He does not rigidly destroy
all inferior animals, but protects during each varying season, as far as
lies in his power, all his productions. He often begins his selection
by some half-monstrous form; or at least by some modification prominent
enough to catch his eye, or to be plainly useful to him. Under nature,
the slightest difference of structure or constitution may well turn the
nicely-balanced scale in the struggle for life, and so be preserved.
How fleeting are the wishes and efforts of man! how short his time!
and consequently how poor will his products be, compared with those
accumulated by nature during whole geological periods. Can we wonder,
then, that nature's productions should be far "truer" in character than
man's productions; that they should be infinitely better adapted to the
most complex conditions of life, and should plainly bear the stamp of
far higher workmanship?

It may be said that natural selection is daily and hourly scrutinising,
throughout the world, every variation, even the slightest; rejecting
that which is bad, preserving and adding up all that is good; silently
and