| → we can see that 1859 1860 1861 1866 1869 |
| OMIT 1872 |
|
| → he finds that 1859 1860 1861 1866 1869 |
| OMIT 1872 |
|
| → in Australia; and 1859 1860 1861 1866 1869 |
| good in Australia: but if most of the Australian trees are dichogamous, the same result would follow as if they bore flowers with separated sexes. 1872 |
|
| → the sexes of 1859 1860 1861 1866 1869 |
| OMIT 1872 |
|
| → on the land there are some hermaphrodites, as 1859 1860 1861 1866 1869 |
| various terrestrial species are hermaphrodites, such as the 1872 |
|
| → case of a 1859 1860 1861 1866 1869 |
| OMIT 1872 |
|
| → We can understand 1859 1860 1861 1866 1869 |
| OMIT 1872 |
|
|
is part of the general law of good being derived from the intercrossing of distinct individuals of the same species. When distinct
species
are crossed the case is
for a
own pollen is
prepotent over foreign pollen; but to this subject we shall return in a future chapter. |
|
| In the case of a
tree covered with
flowers, it may be objected that pollen could seldom be carried from tree to tree, and at most only from flower to flower on the same
and
flowers on the same tree can be considered as distinct individuals only in a limited sense. I believe this objection to be valid, but that nature has largely provided against it by giving to trees a strong tendency to bear flowers with separated sexes. When the sexes are separated, although the male and female flowers may be produced on the same tree,
→we can see that
pollen must be regularly carried from flower to flower; and this will give a better chance of pollen being occasionally carried from tree to tree. That trees belonging to all Orders have their sexes more often separated than other plants, I find to be the case in this country; and at my request Dr. Hooker tabulated the trees of New Zealand, and Dr. Asa Gray those of the United States, and the result was as I anticipated. On the other hand, Dr. Hooker
me that
→he finds that
the rule does not hold
→in Australia; and
I have made these few remarks on
→the sexes of
trees simply to call attention to the subject. |
|
| Turning for a
brief space to animals:
→on the land there are some hermaphrodites, as
land-mollusca and earth-worms; but these all pair. As yet I have not found a single
→case of a
terrestrial animal which
itself.
→We can understand
remarkable fact, which offers so strong a contrast with terrestrial plants,
|
