The crossed plants
were covered with a sheet of bloom, whilst only a single self-fertilised
plant, which was much finer than any of its brethren, flowered. The
crossed and self-fertilised plants had now grown all matted together on
the respective sides of the superficial partitions still separating
them; and in the clump which included the finest self-fertilised plant,
I estimated that the surface covered by the crossed plants was about
nine times as large as that covered by the self-fertilised plants. The
extraordinary superiority of the crossed over the self-fertilised plants
in all five clumps, was no doubt due to the crossed plants at first
having had a decided advantage over the self-fertilised, and then
robbing them more and more of their food during the succeeding seasons.
But we should remember that the same result would follow in a state of
nature even to a greater degree; for my plants grew in ground kept clear
of weeds, so that the self-fertilised had to compete only with the
crossed plants; whereas the whole surface of the ground is naturally
covered with various kinds of plants, all of which have to struggle
together for existence.
The ensuing winter was very severe, and in the following spring (1871)
the plants were again examined. All the self-fertilised were now dead,
with the exception of a single branch on one plant, which bore on its
summit a minute rosette of leaves about as large as a pea.
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