Of the eighty-four capsules on the
self-fertilised plants, all the product of renewed self-fertilisation,
fifty-five (which were alone examined) contained on an average 4.85
seeds per capsule. Therefore the cross-fertilised capsules, compared
with the self-fertilised capsules, yielded seeds in the proportion of
100 to 93. The crossed seeds were relatively heavier than the
self-fertilised seeds. Combining the above data (i.e., number of
capsules and average number of contained seeds), the crossed plants,
compared with the self-fertilised, yielded seeds in the ratio of 100 to
64.
These crossed plants produced, as already stated, fifty-six
spontaneously self-fertilised capsules, and the self-fertilised plants
produced twenty-nine such capsules. The former contained on an average,
in comparison with the latter, seeds in the proportion of 100 to 99.
In Pot 3, on the opposite sides of which a large number of crossed and
self-fertilised seeds had been sown and the seedlings allowed to
struggle together, the crossed plants had at first no great advantage.
At one time the tallest crossed was 25 1/8 inches high, and the tallest
self-fertilised plants 21 3/8. But the difference afterwards became much
greater. The plants on both sides, from being so crowded, were poor
specimens. The flowers were allowed to fertilise themselves
spontaneously under a net; the crossed plants produced thirty-seven
capsules, the self-fertilised plants only eighteen, or as 100 to 47.
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