In order to raise plants of the third generation, a better plan was
followed, and flowers on the crossed plants of the second generation
were selected in which the stamens were too short to reach the stigmas,
so that they could not possibly have been self-fertilised. These flowers
were crossed with pollen from a distinct plant. Flowers on the
self-fertilised plants of the second generation were again
self-fertilised. From the two lots of seeds thus obtained, twenty-one
crossed and nineteen self-fertilised plants of equal age, and forming
the third generation, were raised in fourteen large pots. They were
measured when fully grown, and by an odd chance the average height of
the two lots was exactly the same, namely, 35.96 inches; so that neither
side had the least advantage over the other. To test this result, all
the plants on both sides in ten out of the above fourteen pots were cut
down after they had flowered, and in the ensuing year the stems were
again measured; and now the crossed plants exceeded by a little (namely,
1.7 inches) the self-fertilised. They were again cut down, and on their
flowering for the third time, the self-fertilised plants had a slight
advantage (namely, 1.54 inches) over the crossed. Hence the result
arrived at with these plants during the previous trials was confirmed,
namely, that neither lot had any decided advantage over the other.
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