87
grains, whilst the same number of the supposed crossed seeds weighed
only 3.57 grains, does not look like it. Five seedlings from each lot of
seeds were raised, and the self-fertilised plants, when fully grown,
exceeded in average height by a trifle (namely .4 of an inch) the five
probably crossed plants. I have thought it right to give this case and
the last, because had the supposed crossed plants proved superior to the
self-fertilised in height, I should have assumed without doubt that the
former had really been crossed. As it is, I do not know what to
conclude.
Being much surprised at the two foregoing trials, I determined to make
another, in which there should be no doubt about the crossing. I
therefore fertilised with great care (but as usual without castration)
twenty-four flowers on the supposed crossed plants of the last
generation with pollen from distinct plants, and thus obtained
twenty-one capsules. The self-fertilised plants of the last generation
were allowed to fertilise themselves again under a net, and the
seedlings reared from these seeds formed the third self-fertilised
generation. Both lots of seeds, after germinating on bare sand, were
planted in pairs on the opposite sides of two pots. All the remaining
seeds were sown crowded on opposite sides of a third pot; but as all the
self-fertilised seedlings in this latter pot died before they grew to
any considerable height, they were not measured.
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