Plants of English-crossed and intercrossed parentage, as 100 to 45
seeds.
Plants of intercrossed and self-fertilised parentage, as 100 to 89
seeds.
The superiority in productiveness of the intercrossed plants (that is,
the product of a cross between the grandchildren of the plants which
grew in Brazil) over the self-fertilised, small as it is, is wholly due
to the larger average number of seeds contained in the capsules; for the
intercrossed plants produced fewer capsules in the greenhouse than did
the self-fertilised plants. The great superiority in productiveness of
the English-crossed over the self-fertilised plants is shown by the
larger number of capsules produced, the larger average number of
contained seeds, and the smaller number of empty capsules. As the
English-crossed and intercrossed plants were the offspring of crosses in
every previous generation (as must have been the case from the flowers
being sterile with their own pollen), we may conclude that the great
superiority in productiveness of the English-crossed over the
intercrossed plants is due to the two parents of the former having been
long subjected to different conditions.
The English-crossed plants, though so superior in productiveness, were,
as we have seen, decidedly inferior in height and weight to the
self-fertilised, and only equal to, or hardly superior to, the
intercrossed plants.
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