This also
was necessarily the case with the capsules produced by the cleistogene
flowers of Vandellia.
The fertility of the crossed plants is represented in Table 9/D by 100,
and that of the self-fertilised by the other figures. There are five
cases in which the fertility of the self-fertilised plants is
approximately equal to that of the crossed; nevertheless, in four of
these cases the crossed plants were plainly taller, and in the fifth
somewhat taller than the self-fertilised. But I should state that in
some of these five cases the fertility of the two lots was not strictly
ascertained, as the capsules were not actually counted, from appearing
equal in number and from all apparently containing a full complement of
seeds. In only two instances in the table, namely, with Vandellia and in
the third generation of Dianthus, the capsules on the self-fertilised
plants contained more seed than those on the crossed plants. With
Dianthus the ratio between the number of seeds contained in the
self-fertilised and crossed capsules was as 125 to 100; both sets of
plants were left to fertilise themselves under a net; and it is almost
certain that the greater fertility of the self-fertilised plants was
here due merely to their having varied and become less strictly
dichogamous, so as to mature their anthers and stigmas more nearly at
the same time than is proper to the species.
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