The self-fertilised seedlings grew from the first
quicker than the supposed crossed seedlings, and when both lots were in
full flower the former were from 5 to 6 inches higher than the crossed!
I record in my notes that the self-fertilised seeds from which these
self-fertilised plants were raised were not so well ripened as the
crossed; and this may possibly have caused the great difference in their
growth, in a somewhat analogous manner as occurred with the
self-fertilised plants of the eighth generation of Ipomoea raised from
unhealthy parents. It is a curious circumstance, that two other lots of
the above seeds were sown in pure sand mixed with burnt earth, and
therefore without any organic matter; and here the supposed crossed
seedlings grew to double the height of the self-fertilised, before both
lots died, as necessarily occurred at an early period. We shall
hereafter meet with another case apparently analogous to this of Iberis
in the third generation of Petunia.
The above self-fertilised plants were allowed to fertilise themselves
again under a net, yielding self-fertilised plants of the second
generation, and the supposed crossed plants were crossed by pollen of a
distinct plant; but from want of time this was done in a careless
manner, namely, by smearing one head of expanded flowers over another. I
should have thought that this would have succeeded, and perhaps it did
so; but the fact of 108 of the self-fertilised seeds weighing 4.
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