Of the twenty-six cases, at least two, namely,
those of Adonis and Bartonia, may be wholly excluded, as the trials were
worthless from the extreme unhealthiness of the plants. Inn twelve other
cases (three trials with Eschscholtzia here included) the crossed plants
either were superior in height to the self-fertilised in all the other
generations excepting the one in question, or they showed their
superiority in some different manner, as in weight, fertility, or in
flowering first; or again, the cross-fertilised flowers on the
mother-plant were much more productive of seed than the self-fertilised.
Deducting these fourteen cases, there remain twelve in which the crossed
plants show no well-marked advantage over the self-fertilised. On the
other hand, we have seen that there are fifty-seven cases in which the
crossed plants exceed the self-fertilised in height by at least five per
cent, and generally in a much higher degree. But even in the twelve
cases just referred to, the want of any advantage on the crossed side is
far from certain: with Thunbergia the parent-plants were in an odd
semi-sterile condition, and the offspring grew very unequally; with
Hibiscus and Apium much too few plants were raised for the measurements
to be trusted, and the cross-fertilised flowers of Hibiscus produced
rather more seed than did the self-fertilised; with Vandellia the
crossed plants were a little taller and heavier than the
self-fertilised, but as they were less fertile the case must be left
doubtful.
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