Self-fertilised seedlings
of this latter plant, which were known to have been produced from seeds
not well matured, grew from the first much more quickly than the crossed
plants, which were raised from better matured seeds; so that having thus
once got a great start they were enabled ever afterwards to retain their
advantage. Some of these same seeds of the Iberis were sown on the
opposite sides of pots filled with burnt earth and pure sand, not
containing any organic matter; and now the young crossed seedlings grew
during their short life to double the height of the self-fertilised, in
the same manner as occurred with the above two sets of seedlings of
Petunia which were much crowded and thus exposed to very unfavourable
conditions. We have seen also in the eighth generation of Ipomoea that
the self-fertilised seedlings raised from unhealthy parents grew at
first very much more quickly than the crossed seedlings, so that they
were for a long time much taller, though ultimately beaten by them.
4, 5, 6. Eschscholtzia californica.
Four sets of measurements are given in Table 7/A. In one of these the
crossed plants exceed the self-fertilised in average height, so that
this is not one of the exceptions here to be considered. In two other
cases the crossed equalled the self-fertilised in height within five per
cent; and in the fourth case the self-fertilised exceeded the crossed by
above this limit.
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