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Darwin, Charles, 1809-1882

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


According to Vaucher and Wirtgen, the three forms coexist in all parts of
Europe. Some friends gathered for me in North Wales a number of twigs from
separate plants growing near one another, and classified them. My son did the
same in Hampshire, and here is the result:--
TABLE 4.22. Lythrum salicaria. Classification according to form of flower.
Column 1: Place of origin.
Column 2: Long-styled.
Column 3: Mid-styled.
Column 4: Short-styled.
Column 5: Total.
North Wales : 95 : 97 : 72 : 264.
Hampshire : 53 : 38 : 38 : 129.
Total : 148 : 135 : 110 : 393.
If twice or thrice the number had been collected, the three forms would probably
have been found nearly equal; I infer this from considering the above figures,
and from my son telling me that if he had collected in another spot, he felt
sure that the mid-styled plants would have been in excess. I several times sowed
small parcels of seed, and raised all three forms; but I neglected to record the
parent-form, excepting in one instance, in which I raised from short-styled seed
twelve plants, of which only one turned out long-styled, four mid-styled, and
seven short-styled.
Two plants of each form were protected from the access of insects during two
successive years, and in the autumn they yielded very few capsules and presented
a remarkable contrast with the adjoining uncovered plants, which were densely
covered with capsules.


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