--Viscaria oculata.
Twelve flowers were crossed with pollen from another plant, and yielded
ten capsules, containing by weight 5.77 grains of seeds. Eighteen
flowers were fertilised with their own pollen and yielded twelve
capsules, containing by weight 2.63 grains. Therefore the seeds from an
equal number of crossed and self-fertilised flowers would have been in
weight as 100 to 38. I had previously selected a medium-sized capsule
from each lot, and counted the seeds in both; the crossed one contained
284, and the self-fertilised one 126 seeds; or as 100 to 44. These seeds
were sown on opposite sides of three pots, and several seedlings raised;
but only the tallest flower-stem of one plant on each side was measured.
The three on the crossed side averaged 32.5 inches, and the three on the
self-fertilised side 34 inches in height; or as 100 to 104. But this
trial was on much too small a scale to be trusted; the plants also grew
so unequally that one of the three flower-stems on the crossed plants
was very nearly twice as tall as that on one of the others; and one of
the three flower-stems on the self-fertilised plants exceeded in an
equal degree one of the others.
In the following year the experiment was repeated on a larger scale: ten
flowers were crossed on a new set of plants and yielded ten capsules
containing by weight 6.54 grains of seed. Eighteen spontaneously
self-fertilised capsules were gathered, of which two contained no seed;
the other sixteen contained by weight 6.
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