| → each 1859 1860 1861 1866 |
| between the several kinds of trees, each 1869 1872 |
|
| → compared to the action and reaction 1859 1860 |
| where each shall fall compared to that 1861 1866 1869 1872 |
|
| → innumerable 1859 1860 |
| action and reaction of the innumerable 1861 1866 1869 1872 |
|
| → almost invariably will 1859 1860 1861 1866 |
| will almost invariably 1869 1872 |
|
|
have gone on during long
→each
annually scattering its seeds by the thousand; what war between insect and
insects, snails, and other animals with birds and beasts of
striving to increase,
all feeding on each
or on the
their seeds and seedlings, or on the other plants which first clothed the ground and thus checked the growth of the trees! Throw up a handful of feathers, and all
fall to the ground according to definite laws; but how simple is
problem
→compared to the action and reaction
of the
→innumerable
plants and animals which have determined, in the course of centuries, the proportional numbers and kinds of trees now growing on the old Indian ruins! |
|
| The dependency of one organic being on another, as of a parasite on its prey, lies generally between beings remote in the scale of nature. This is
the case with those which may
said to struggle with each other for existence, as in the case of locusts and grass-feeding quadrupeds. But the struggle
→almost invariably will
be most severe between the individuals of the same species, for they frequent the same districts, require the same food, and are exposed to the same dangers. In the case of varieties of the same species, the struggle will generally be almost equally severe, and we sometimes see the contest soon decided: for instance, if several varieties of wheat be sown together, and the mixed seed be resown, some of the varieties which best suit the soil or climate, or are naturally the most fertile, will beat the others and so yield more seed, and will consequently in a few years
supplant the other varieties. To keep up a mixed stock of even such extremely close varieties as the
sweet-peas, they must be each year harvested separately, and the seed then mixed in due
|
