| When the stamens of a flower suddenly spring towards the pistil, or slowly move one after the other towards it, the contrivance seems adapted solely to ensure self-fertilisation; and no doubt it is useful for this end:
the agency of insects is often required to cause the stamens to spring forward, as
has shown to be the case with the barberry; and
in this very genus, which seems to have a special contrivance for self-fertilisation, it is well known
if
closely-allied forms or varieties are planted near each other, it is hardly possible to raise pure seedlings, so largely do they naturally cross. In
other cases, far from
being
→any aids for self-fertilisation,
there are special
→as
I could show from the
of
Sprengel and
→from
my own
→which effectually prevent the stigma receiving pollen from its own flower:
for instance, in Lobelia fulgens, there is a really beautiful and elaborate contrivance by which
→every one of
the infinitely numerous pollen-granules are swept out of the conjoined anthers of each flower, before the stigma of that individual flower is ready to receive them; and as this flower is never visited, at least in my garden, by insects, it never sets a seed, though by placing pollen from one flower on the stigma of another, I raised plenty of
↑
In very many other cases, though there
no special mechanical contrivance to prevent the stigma
→of a flower receiving its own pollen,
yet, as
|
