From the flowers
thus treated thirty seedlings were raised, and all these without
exception bore reddish flowers; so that the effect of the plant's own
pollen, though placed on the stigmas twenty-four hours previously, was
quite destroyed by that of the red variety. It should, however, be
observed that these plants are dimorphic, and that the second union was
a legitimate one, whilst the first was illegitimate; but flowers
illegitimately fertilised with their own pollen yield a moderately fair
supply of seeds.
We have hitherto considered only the prepotent fertilising power of
pollen from a distinct variety over a plants' own pollen,--both kinds of
pollen being placed on the same stigma. It is a much more remarkable
fact that pollen from another individual of the same variety is
prepotent over a plant's own pollen, as shown by the superiority of the
seedlings raised from a cross of this kind over seedlings from
self-fertilised flowers. Thus in Tables 7/A, B, and C, there are at
least fifteen species which are self-fertile when insects are excluded;
and this implies that their stigmas must receive their own pollen;
nevertheless, most of the seedlings which were raised by fertilising the
non-castrated flowers of these fifteen species with pollen from another
plant were greatly superior, in height, weight, and fertility, to the
self-fertilised offspring. (10/40.
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