This was the
first plant on which I experimented, and I had not then formed any
regular scheme of operation. When the two lots were in full flower, I
measured roughly a large number of plants but record only that the
crossed were on an average fully 4 inches taller than the
self-fertilised. Judging from subsequent measurements, we may assume
that the crossed plants were about 28 inches, and the self-fertilised
about 24 inches in height; and this will give us a ratio of 100 to 86.
Out of a large number of plants, four of the crossed ones flowered
before any one of the self-fertilised plants.
Thirty flowers on these crossed plants of the first generation were
again crossed with pollen from a distinct plant of the same lot, and
yielded twenty-nine capsules, containing on an average 55.62 seeds, with
a maximum in one of 110 seeds.
Thirty flowers on the self-fertilised plants were again self-fertilised;
eight of them with pollen from the same flower, and the remainder with
pollen from another flower on the same plant; and these produced
twenty-two capsules, containing on an average 35.95 seeds, with a
maximum in one of sixty-one seeds. We thus see, judging by the number of
seeds per capsule, that the crossed plants again crossed were more
productive than the self-fertilised again self-fertilised, in the ratio
of 100 to 65. Both the crossed and self-fertilised plants, from having
grown much crowded in the two beds, produced less fine capsules and
fewer seeds than did their parents.
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