On the following year eight flowers on
plants of the Brazilian stock of self-fertilised parentage (i.e.,
grandchildren of the plants which grew in Brazil) were again
self-fertilised, and produced five capsules, containing on an average
27.4 seeds, with a maximum in one of forty-two seeds; so that their
self-fertility had evidently increased greatly by being reared for two
generations in England. On the whole we may conclude that plants of the
Brazilian stock are much more self-fertile in this country than in
Brazil, and less so than plants of the English stock in England; so that
the plants of Brazilian parentage retained by inheritance some of their
former sexual constitution. Conversely, seeds from English plants sent
by me to Fritz Muller and grown in Brazil, were much more self-fertile
than his plants which had been cultivated there for several generations;
but he informs me that one of the plants of English parentage which did
not flower the first year, and was thus exposed for two seasons to the
climate of Brazil, proved quite self-sterile, like a Brazilian plant,
showing how quickly the climate had acted on its sexual constitution.
Abutilon darwinii.
Seeds of this plant were sent me by Fritz Muller, who found it, as well
as some other species of the same genus, quite sterile in its native
home of South Brazil, unless fertilised with pollen from a distinct
plant, either artificially or naturally by humming-birds.
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