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Darwin, Charles, 1809-1882

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


PLANT 23.
This short-styled plant produced perfectly sound pollen. During 1866 it was
freely and legitimately fertilised by the other illegitimate plants specified
under the last experiment, and eight capsules yielded an average of 113.5 seeds,
with a maximum of 123 and a minimum of 93. Hence this plant exceeded the normal
standard, producing no less than 136 per cent of seeds.
PLANT 24.
This long-styled plant produced pollen which seemed under the microscope sound;
but some of the grains did not swell when placed in water. During 1864 it was
legitimately fertilised by legitimate and illegitimate plants in the same manner
as Plant 22, but yielded an average, from ten capsules, of only 55 seeds, with a
maximum of 88 and a minimum of 24, thus attaining 59 per cent of the normal
fertility. This low degree of fertility, I presume, was owing to the
unfavourable season; for during 1866, when legitimately fertilised by
illegitimate plants in the manner described under Number 22, it yielded an
average, from eight capsules, of 82 seeds, with a maximum of 120 and a minimum
of 67, thus producing 88 per cent of the normal number of seeds.
PLANT 25.
The pollen of this long-styled plant contained a moderate number of poor and
shrivelled grains; and this is a surprising circumstance, as it yielded an
extraordinary number of seeds.


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