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Darwin, Charles, 1809-1882

"The Different Forms of Flowers on Plants of the Same Species"

As in fertilising flowers there will always be some failures, it would
have been advisable to have repeated each of the eighteen unions a score of
times; but the labour would have been too great; as it was, I made 223 unions,
i.e. on an average I fertilised above a dozen flowers in the eighteen different
methods. Each flower was castrated; the adjoining buds had to be removed, so
that the flowers might be safely marked with thread, wool, etc.; and after each
fertilisation the stigma was examined with a lens to see that there was
sufficient pollen on it. Plants of all three forms were protected during two
years by large nets on a framework; two plants were used during one or both
years, in order to avoid any individual peculiarity in a particular plant. As
soon as the flowers had withered, the nets were removed; and in the autumn the
capsules were daily inspected and gathered, the ripe seeds being counted under
the microscope. I have given these details that confidence may be placed in the
following tables, and as some excuse for two blunders which, I believe, were
made. These blunders are referred to, with their probable cause, in two
footnotes to the tables. The erroneous numbers, however, are entered in the
tables, that it may not be supposed that I have in any one instance tampered
with the results.
A few words explanatory of the three tables must be given.


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