It
may, however, be worth mentioning that the self-fertilised plants showed
some tendency to flower before the crossed plants: this occurred with
all three pairs of the first generation; and with the cut down plants of
the third generation, a self-fertilised plant flowered first in nine out
of the twelve pots, whilst in the remaining three pots a crossed plant
flowered first.
If we consider all the plants of the three generations taken together,
the thirty-four crossed plants average 35.98, and the thirty-four
self-fertilised plants 36.39 inches in height; or as 100 to 101. We may
therefore conclude that the two lots possessed equal powers of growth;
and this I believe to be the result of long-continued
self-fertilisation, together with exposure to similar conditions in each
generation, so that all the individuals had acquired a closely similar
constitution.
30. GRAMINACEAE.--Zea mays.
This plant is monoecious, and was selected for trial on this account, no
other such plant having been experimented on. (6/8. Hildebrand remarks
that this species seems at first sight adapted to be fertilised by
pollen from the same plant, owing to the male flowers standing above the
female flowers; but practically it must generally be fertilised by
pollen from another plant, as the male flowers usually shed their pollen
before the female flowers are mature: 'Monatsbericht der K.
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