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Darwin, Charles, 1809-1882

"Effects of Cross and Self Fertilisation in the Vegetable Kingdom"

This latter evil, the greatest of all to any
organism, would have been much lessened by their becoming
hermaphrodites, though with the contingent disadvantage of frequent
self-fertilisation. By what graduated steps an hermaphrodite condition
was acquired we do not know. But we can see that if a lowly organised
form, in which the two sexes were represented by somewhat different
individuals, were to increase by budding either before or after
conjugation, the two incipient sexes would be capable of appearing by
buds on the same stock, as occasionally occurs with various characters
at the present day. The organism would then be in a monoecious
condition, and this is probably the first step towards hermaphroditism;
for if very simple male and female flowers on the same stock, each
consisting of a single stamen or pistil, were brought close together and
surrounded by a common envelope, in nearly the same manner as with the
florets of the Compositae, we should have an hermaphrodite flower.
There seems to be no limit to the changes which organisms undergo under
changing conditions of life; and some hermaphrodite plants, descended as
we must believe from aboriginally diclinous plants, have had their sexes
again separated. That this has occurred, we may infer from the presence
of rudimentary stamens in the flowers of some individuals, and of
rudimentary pistils in the flowers of other individuals, for example in
Lychnis dioica.


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