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The violet wood-sorrel produces two sorts of perfect flowers
reciprocally adapted to each other, but on different plants in
the same neighborhood. The two are essentially alike, except in
arrangement of stamens and pistil; one flower having high anthers
and low stigmas, the other having lower anthers and higher
stigmas; and as the high stigmas are fertile only when pollenized
with grains from a flower having high anthers, it is evident
insect aid to transfer pollen is indispensable here. Small bees,
which visit these blossoms abundantly, are their benefactors;
although there is nothing to prevent pollen from falling on the
stigmas of the short-styled form. Hildebrand proved that
productiveness is greatest, or exists only, after legitimate
fertilization. To accomplish cross-pollination, many plants bear
flowers of opposite sexes on different individuals; but the
violet wood-sorrel's plan, utilized by the bluet and
partridge-vine also, has the advantage in that both kinds of its
flowers are fruitful.


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