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inches in height; or as 100 to 99. The self-fertilised plants from the
cleistogene flowers averaged 4.06 inches in height; so that the crossed
were in height to these latter plants as 100 to 94.
I determined to compare again the growth of plants raised from crossed
and self-fertilised perfect flowers, and obtained two fresh lots of
seeds. These were sown on opposite sides of five pots, but they were not
sufficiently thinned, so that they grew rather crowded. When fully
grown, all those above 2 inches in height were selected, all below this
standard being rejected; the former consisted of forty-seven crossed and
forty-one self-fertilised plants; thus a greater number of the crossed
than of the self-fertilised plants grew to a height of above 2 inches.
Of the crossed plants, the twenty-four tallest were on an average 3.6
inches in height; whilst the twenty-four tallest self-fertilised plants
were 3.38 inches in average height; or as 100 to 94. All these plants
were then cut down close to the ground, and the forty-seven crossed
plants weighed 1090.3 grains, and the forty-one self-fertilised plants
weighed 887.4 grains. Therefore an equal number of crossed and
self-fertilised would have been to each other in weight as 100 to 97.
From these several facts we may conclude that the crossed plants had
some real, though very slight, advantage in height and weight over the
self-fertilised plants, when grown in competition with one another.
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