The vast number of the small shrivelled grains in the above two cases explains
the fact that, though equal-styled plants are generally fertile in a high
degree, yet some of them yield few seeds. I may add that my son compared, in
1875, the grains from two white-flowered plants, in both of which the pistil
projected above the anthers, but neither were properly long-styled or equal-
styled; and in the one in which the stigma projected most, the grains were in
diameter to those in the other plant, in which the stigma projected less, as 100
to 88; whereas the difference between the grains from perfectly characterised
long-styled and short-styled plants is as 100 to 57. So that these two plants
were in an intermediate condition. To return to the 17 plants in the first line
of Table 5.31: from the relative position of their stigmas and anthers, they
could hardly fail to fertilise themselves; and accordingly four of them
spontaneously yielded no less than 180 capsules; of these Mr. Horwood selected
eight fine capsules for sowing; and they included on an average 54.8 seeds, with
a maximum of 72. He gave me thirty other capsules, taken by hazard, of which
twenty-seven contained good seeds, averaging 35.5, with a maximum of 70; but if
six poor capsules, each with less than 13 seeds, be excluded, the average rises
to 42.
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