| → 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 |
|
| → on 1859 1860 1861 1866 1869 |
| is intelligible on 1872 |
|
| → by considering the medium in which terrestrial animals live, and 1859 1860 1861 1866 1869 |
| for owing to 1872 |
|
| → for we know of 1859 1860 1861 1866 1869 |
| there are 1872 |
|
| → in the case of 1859 1860 1861 1866 1869 |
| with 1872 |
|
|
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,
→on
the view of an occasional cross being
→by considering the medium in which terrestrial animals live, and
the nature of the fertilising
→for we know of
no means, analogous to the action of insects and of the wind
→in the case of
plants, by which an occasional cross could be effected with terrestrial animals without the concurrence of two individuals. Of aquatic animals, there are many self-fertilising hermaphrodites; but here
|
