How much proportional weight ought to be attributed to these two
agencies,--the one tending to injure the self-fertilised offspring, and
the other to benefit the crossed offspring,--cannot be determined. But
we shall immediately see that the greater part of the benefit, as far as
increased fertility is concerned, must be attributed to the cross having
been made with a fresh stock.
Primula veris.
EQUAL-STYLED AND RED-FLOWERED VAR.
I have described in my paper 'On the Illegitimate Unions of Dimorphic
and Trimorphic Plants' this remarkable variety, which was sent to me
from Edinburgh by Mr. J. Scott. It possessed a pistil proper to the
long-styled form, and stamens proper to the short-styled form; so that
it had lost the heterostyled or dimorphic character common to most of
the species of the genus, and may be compared with an hermaphrodite form
of a bisexual animal. Consequently the pollen and stigma of the same
flower are adapted for complete mutual fertilisation, instead of its
being necessary that pollen should be brought from one form to another,
as in the common cowslip. From the stigma and anthers standing nearly on
the same level, the flowers are perfectly self-fertile when insects are
excluded. Owing to the fortunate existence of this variety, it is
possible to fertilise its flowers in a legitimate manner with their own
pollen, and to cross other flowers in a legitimate manner with pollen
from another variety or fresh stock.
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