veris, when both species are illegitimately fertilised. If we
judge of the relative fertility of the two kinds of unions by the average number
of seeds per capsule, the ratio is as 100 to 75. But this latter number is
probably much too high, as many of the seeds produced by the illegitimately
fertilised long-styled flowers were so small that they probably would not have
germinated, and ought not to have been counted. Several long-styled and short-
styled plants were protected from the access of insects, and must have been
spontaneously self-fertilised. They yielded altogether only six capsules,
containing any seeds; and their average number was only 7.8 per capsule. Some,
moreover, of these seeds were so small that they could hardly have germinated.
Herr W. Breitenbach informs me that he examined, in two sites near the Lippe (a
tributary of the Rhine), 894 flowers produced by 198 plants of this species; and
he found 467 of these flowers to be long-styled, 411 short-styled, and 16 equal-
styled. I have heard of no other instance with heterostyled plants of equal-
styled flowers appearing in a state of nature, though far from rare with plants
which have been long cultivated. It is still more remarkable that in eighteen
cases the same plant produced both long-styled and short-styled, or long-styled
and equal-styled flowers; and in two out of the eighteen cases, long-styled,
short-styled, and equal-styled flowers.
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