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Darwin, Charles, 1809-1882

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

These plants, therefore, not only have lost their proper heterostyled
structure and peculiar functional powers, but have acquired an abnormal grade of
fertility--unless, indeed, their high fertility may be accounted for by the
stigmas receiving pollen from the circumjacent anthers at exactly the most
favourable period.
With respect to Mr. Duck's lot in Table 5.31, seed was saved from a single
plant, of which the form was not observed, and this produced nine equal-styled
and twenty long-styled plants. The equal-styled resembled in all respects those
previously described; and eight of their capsules spontaneously self-fertilised
contained on an average 44.4 seeds, with a maximum of 61 and a minimum of 23. In
regard to the twenty long-styled plants, the pistil in some of the flowers did
not project quite so high as in ordinary long-styled flowers; and the stigmas,
though properly elongated, were smooth; so that we have here a slight approach
in structure to the pistil of the short-styled form. Some of these long-styled
plants also approached the equal-styled in function; for one of them produced no
less than fifteen spontaneously self-fertilised capsules, and of these eight
contained, on an average, 31.7 seeds, with a maximum of 61. This average would
be rather low for a long-styled plant artificially fertilised with its own
pollen, but is high for one spontaneously self-fertilised.


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