But the best evidence of a want of
correspondence between the number of seeds produced by crossed and
self-fertilised flowers, and the vigour of the offspring raised from
them, is afforded by the plants of the Brazilian and European stocks of
Eschscholtzia, and likewise by certain individual plants of Reseda
odorata; for it might have been expected that the seedlings from plants,
the flowers of which were excessively self-sterile, would have profited
in a greater degree by a cross, than the seedlings from plants which
were moderately or fully self-fertile, and therefore apparently had no
need to be crossed. But no such result followed in either case: for
instance, the crossed and self-fertilised offspring from a highly
self-fertile plant of Reseda odorata were in average height to each
other as 100 to 82; whereas the similar offspring from an excessively
self-sterile plant were as 100 to 92 in average height.
With respect to the innate fertility of the plants of crossed and
self-fertilised parentage, given in the previous Table 9/D--that is, the
number of seeds produced by both lots when their flowers were fertilised
in the same manner,--nearly the same remarks are applicable, in
reference to the absence of any close correspondence between their
fertility and powers of growth, as in the case of the plants in the
Tables 9/F and 9/G, just considered. Thus the crossed and
self-fertilised plants of Ipomoea, Papaver, Reseda odorata, and
Limnanthes were almost equally fertile, yet the former exceeded
considerably in height the self-fertilised plants.
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