But nevertheless the anomaly was repeated, and the aberrant
individuals were once more isolated before flowering. The third
generation repeated the second, but produced sixty twisted stems on some
1,600 individuals. The result was very striking and quite sufficient for
all further researches, but the normal condition of the race was not
reached. This was the case only after I had discovered the bad effects
of growing too many plants in a limited space. In the fourth generation
I restricted my whole culture to about 100 individuals, and by this
simple [405] means at once got up to 34% of twisted stems. This
proportion has since remained practically the same. I have selected and
isolated my plants during five succeeding generations, but without any
further result, the percentage of twisted stems fluctuating between 30
and about 45 according to the size of the cultures and the favorableness
or unfavorableness of the weather.
It is very interesting to note that all depends on the question whether
one has the good fortune of finding a rich race or not, as this
pedigree-culture shows. Afterwards everything depends on treatment and
very little on selection. As soon as the treatment becomes adequate, the
full strength of the race at once displays itself, but afterwards no
selection is able to improve it to any appreciable amount.
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