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Darwin, Charles, 1809-1882

"Effects of Cross and Self Fertilisation in the Vegetable Kingdom"

5 seeds; or as 100 to
106. Seedlings were raised from these seeds. In one of the pots all the
self-fertilised plants died whilst quite young; in the two others, the
measurements were as follows:
TABLE 4/43. Adonis aestivalis.
Heights of plants measured in inches.
Column 1: Number (Name) of Pot.
Column 2: Crossed Plants.
Column 3: Self-fertilised Plants.
Pot 1 : 14 : 13 4/8.
Pot 1 : 13 4/8 : 13 4/8.
Pot 2 : 16 2/8 : 15 2/8.
Pot 2 : 13 2/8 : 15.
Total : 57.00 : 57.25.
The average height of the four crossed plants is 14.25, and that of the
four self-fertilised plants 14.31; or as 100 to 100.4; so that they were
in fact of equal height. According to Professor H. Hoffman, this plant
is proterandrous (4/7. 'Zur Speciesfrage' 1875 page 11.); nevertheless
it yields plenty of seeds when protected from insects.
Delphinium consolida.
It has been said in the case of this plant, as of so many others, that
the flowers are fertilised in the bud, and that distinct plants or
varieties can never naturally intercross. (4/8. Decaisne
'Comptes-Rendus' July 1863 page 5.) But this is an error, as we may
infer, firstly from the flowers being proterandrous,--the mature stamens
bending up, one after the other, into the passage which leads to the
nectary, and afterwards the mature pistils bending in the same
direction; secondly, from the number of humble-bees which visit the
flowers (4/9.


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