But the experiments will show whether this effect holds good against the
influences which tend to change the direction of the development of the
anomaly during the time of germination. [398] The result of my attempt
has shown that the choice of the seeds has a manifest influence upon the
ultimate development of the monstrosity, but that this influence is not
strong enough to overwhelm all other factors.
The choice of the fullest or smallest crowns may be repeated during
succeeding generations, and each time compared with a culture under
average conditions. By this means we come to true selection-experiments,
and these result in a notable and rapid change of the whole strain. By
selecting the brightest crowns I have come up in three years from 40 to
90 and ultimately to 120 converted stamens in the best flower of my
culture, and in selecting the smallest crowns I was able in three years
to exclude nearly all good crowns, and to make cultures in which heads
with less than half-filled crowns constituted the majority. But such
selected strains always remain very sensitive to treatment, and by
changing the conditions the effect may be wholly lost in a single year,
or even turned in the contrary direction. In other words, the anomaly is
more dependent on external conditions during the germinating period than
on the choice of the seeds, providing these belong to the pistilloid
variety and have not deteriorated by some crossing with other sorts.
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