I allude to
this fact because botanists in speaking of the fertilisation of various flowers,
often refer to the wind or to insects as if the alternative were indifferent.
This view, according to my experience, is entirely erroneous. When the wind is
the agent in carrying pollen, either from one sex to the other, or from
hermaphrodite to hermaphrodite, we can recognise structure as manifestly adapted
to its action as to that of insects when these are the carriers. We see
adaptation to the wind in the incoherence of the pollen,--in the inordinate
quantity produced (as in the Coniferae, Spinage, etc.),--in the dangling anthers
well fitted to shake out the pollen,--in the absence or small size of the
perianth,--in the protrusion of the stigmas at the period of fertilisation,--in
the flowers being produced before they are hidden by the leaves,--and in the
stigmas being downy or plumose (as in the Gramineae, Docks, etc), so as to
secure the chance-blown grains. In plants which are fertilised by the wind, the
flowers do not secrete nectar, their pollen is too incoherent to be easily
collected by insects, they have not bright-coloured corollas to serve as guides,
and they are not, as far as I have seen, visited by insects. When insects are
the agents of fertilisation (and this is incomparably the more frequent case
with hermaphrodite plants), the wind plays no part, but we see an endless number
of adaptations to ensure the safe transport of the pollen by the living workers.
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