Lastly, legitimate unions effected by me between
the three forms gave, as may be seen in the following tables, for the long-
styled an average of 90 seeds, for the mid-styled 117, and for the short-styled
71. So that we have good concurrent evidence of a difference in the average
production of seed by the three forms. To show that the unions effected by me
often produced their full effect and may be trusted, I may state that one mid-
styled capsule yielded 151 good seeds, which is the same number as in the finest
wild capsule which I examined. Some artificially fertilised short- and long-
styled capsules produced a greater number of seeds than was ever observed by me
in wild plants of the same forms, but then I did not examine many of the latter.
This plant, I may add, offers a remarkable instance, how profoundly ignorant we
are of the life-conditions of a species. Naturally it grows "in wet ditches,
watery places, and especially on the banks of streams," and though it produces
so many minute seeds, it never spreads on the adjoining land; yet, when planted
in my garden, on clayey soil lying over chalk, and which is so dry that a rush
cannot be found, it thrives luxuriantly, grows to above 6 feet in height,
produces self-sown seedlings, and (which is a severer test) is as fertile as in
a state of nature. Nevertheless it would be almost a miracle to find this plant
growing spontaneously on such land as that in my garden.
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