07 seeds per
capsule. The sixty-four flowers with only a little pollen placed on one
side of the stigma yielded sixty-three capsules, and excluding one from
the same cause as before, the remainder contained on an average 5.129
seeds. So that the flowers fertilised with little pollen yielded rather
more capsules and seeds than did those fertilised with an excess; but
the difference is too slight to be of any significance. On the other
hand, the seeds produced by the flowers with an excess of pollen were a
little heavier of the two; for 170 of them weighed 79.67 grains, whilst
170 seeds from the flowers with very little pollen weighed 79.20 grains.
Both lots of seeds having been placed on damp sand presented no
difference in their rate of germination. We may therefore conclude that
my experiments were not affected by any slight difference in the amount
of pollen used; a sufficiency having been employed in all cases.
The order in which our subject will be treated in the present volume is
as follows. A long series of experiments will first be given in Chapters
2 to 6. Tables will afterwards be appended, showing in a condensed form
the relative heights, weights, and fertility of the offspring of the
various crossed and self-fertilised species. Another table exhibits the
striking results from fertilising plants, which during several
generations had either been self-fertilised or had been crossed with
plants kept all the time under closely similar conditions, with pollen
taken from plants of a distinct stock and which had been exposed to
different conditions.
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