UNDER THE APPLE-TREES 
well as the four-toed; the downy as well as his 
larger and more powerful brother, the hairy; the 
creepers and the nuthatches, with their slender 
beaks, as well as those with powerful beaks; animals 
without legs, as snakes, as well as animals with 
legs; and the bipeds flourish as well as the quad- 
rupeds; birds without the power of flight also flour- 
ish; animals with horns succeed no better than ani- 
mals without horns. Natural selection works in 
each species, weeding out the weak and the imper- 
fect, but the competition among species has only 
the effect of clinching and developing the species, 
not in originating new ones. 
The struggle for life, outside of man’s disturb- 
ing influence, is not so much a struggle of the weak 
against the strong, or of one form against another, 
as it is a struggle of the plant or animal with its 
environment. If there were but one plant, or one 
animal, or one tree on the earth, the life of that one 
individual would be a struggle, much more, of 
course, in some parts of the earth, and in certain 
climates, than in others, and the severer the strug- 
gle within certain limits, the greater the tenacity 
of life. An oak-tree growing amid the rocks and 
on a scanty soil has tougher fibre but less size and 
grace of form than the tree growing on an alluvial 
plain. A life is made strong by the obstacles it 
overcomes. We do not feel the force of the wind or 
the tide when we go with them. The balloonist rides 
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