[1. Dianthus caryophyllus (third generation).
This plant was experimented on during four generations, in three of
which the crossed plants exceeded in height the self-fertilised
generally by much more than five per cent; and we have seen under Table
7/C that the offspring from the plants of the third self-fertilised
generation crossed by a fresh stock profited in height and fertility to
an extraordinary degree. But in this third generation the crossed plants
of the same stock were in height to the self-fertilised only as 100 to
99, that is, they were practically equal. Nevertheless, when the eight
crossed and eight self-fertilised plants were cut down and weighed, the
former were to the latter in weight as 100 to 49! There can therefore be
not the least doubt that the crossed plants of this species are greatly
superior in vigour and luxuriance to the self-fertilised; and what was
the cause of the self-fertilised plants of the third generation, though
so light and thin, growing up so as almost to equal the crossed in
height, I cannot explain.
2. Lobelia fulgens (first generation).
The crossed plants of this generation were much inferior in height to
the self-fertilised, in the proportion of 100 to 127. Although only two
pairs were measured, which is obviously much too few to be trusted, yet
from other evidence given under the head of this species, it is certain
that the self-fertilised plants were very much more vigorous than the
crossed.
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