| → himself, the flowers 1866 |
| it, 1869 1872 |
|
| → in our imaginary case: 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
| → they can, with a very little more trouble, 1859 1860 1861 1866 1869 |
| with a very little more trouble, they can 1872 |
|
| → it may be believed that an accidental deviation 1866 |
| I can see no reason to doubt that an accidental deviation 1859 1860 1861 |
| it may be believed that under certain circumstances individual differences 1869 1872 |
|
| → size and form 1859 1860 1861 1866 |
| curvature or length 1869 1872 |
|
| → body, or in the curvature and length of the 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
|
be advantageous to a plant to produce stamens alone in one flower or on one whole plant, and pistils alone in another flower or on another plant. In plants under culture and placed under new conditions of life, sometimes the male organs and sometimes the female organs become more or less impotent; now if we suppose this to occur in ever so slight a degree under nature,
as pollen is already carried regularly from flower to flower, and as a more complete separation of the sexes of our plant would be advantageous on the principle of the division of labour, individuals with this tendency more and more increased, would be continually favoured or selected, until at last a complete separation of the sexes
be effected. It would take up too much space to show the various steps, through dimorphism and other means, by which the separation of the sexes in plants of various kinds is apparently now in progress; but I may add that some of the species of holly in North
are, according to Asa Gray, in an
condition, or, as he expresses
→himself, the flowers
are more or less diœciously polygamous. |
|
| Let us now turn to the nectar-feeding
→in our imaginary case:
we may suppose the
of which we have been slowly increasing the nectar by continued selection, to be a common plant; and that certain insects depended in main part on its nectar for food. I could give many
showing how anxious bees are to save
for instance, their habit of cutting holes and sucking the nectar at the bases of certain flowers, which
→they can, with a very little more trouble,
enter by the mouth. Bearing such facts in mind,
→it may be believed that an accidental deviation
in the
→size and form
of the
→body, or in the curvature and length of the
proboscis, &c.,
too slight to be appreciated by us, might profit a bee or other insect, so
|
