Several anthers from flowers
on the crossed and self-fertilised plants of the eighth generation were
compared under the microscope; and those from the former were generally
longer and plainly broader than the anthers of the self-fertilised
plants. The quantity of pollen contained in one of the latter was, as
far as could be judged by the eye, about half of that contained in one
from a crossed plant. The impaired fertility of the self-fertilised
plants of the eighth generation was also shown in another manner, which
may often be observed in hybrids--namely, by the first-formed flowers
being sterile. For instance, the fifteen first flowers on a
self-fertilised plant of one of the later generations were carefully
fertilised with their own pollen, and eight of them dropped off; at the
same time fifteen flowers on a crossed plant growing in the same pot
were self-fertilised, and only one dropped off. On two other crossed
plants of the same generation, several of the earliest flowers were
observed to fertilise themselves and to produce capsules. In the plants
of the ninth, and I believe of some previous generations, very many of
the flowers, as already stated, were slightly monstrous; and this
probably was connected with their lessened fertility.
All the self-fertilised plants of the seventh generation, and I believe
of one or two previous generations, produced flowers of exactly the same
tint, namely, of a rich dark purple.
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