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Darwin, Charles, 1809-1882

"The Different Forms of Flowers on Plants of the Same Species"


Thus we can understand the meaning of the torsion of the styles in the long-
styled flowers alone, as well as their divergence in the short-styled flowers.
One other point is worth notice. In botanical works many flowers are said to be
fertilised in the bud. This statement generally rests, as far as I can discover,
on the anthers opening in the bud; no evidence being adduced that the stigma is
at this period mature, or that it is not subsequently acted on by pollen brought
from other flowers. In the case of Cephalanthera grandiflora I have shown that
precocious and partial self-fertilisation, with subsequent full fertilisation,
is the regular course of events. (3/4. 'Fertilisation of Orchids' page 108; 2nd
edition 1877 page 84.) The belief that the flowers of many plants are fertilised
in the bud, that is, are perpetually self-fertilised, is a most effectual bar to
understanding their real structure. I am, however, far from wishing to assert
that some flowers, during certain seasons, are not fertilised in the bud; for I
have reason to believe that this is the case. A good observer, resting his
belief on the usual kind of evidence, states that in Linum Austriacum (which is
heterostyled, and is considered by Planchon as a variety of L. perenne) the
anthers open the evening before the expansion of the flowers, and that the
stigmas are then almost always fertilised.


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