From this reason it is as interesting to appreciate the hereditary
position of the atavists of twisted varieties as it was for the
red-flowered descendants of the striped flowers. In order to ascertain
this relation it is only necessary to isolate some of them during the
blooming-period. I made this experiment in the summer of 1900 with the
eighth generation of my race, and contrived [407] to isolate three
groups of plants by the use of parchment bags, covering them
alternately, so the flowers of only one group were accessible to
insects, at a time. I made three groups, because the atavists show two
different types. Some specimens have decussate stems, others bear all
their leaves in whorls of three, but in respect to the hereditary
tendency of the twisting character this difference does not seem to be
of any importance.
In this way I got three lots of seeds and sowed enough of them to have
three groups of plants each containing about 150-200 well developed
stems. Among these I counted the twisted individuals, and found nearly
the same numbers for all three. The twisted parents gave as many as 41%
twisted children, but the decussate atavists gave even somewhat more,
viz., 44%, while the ternate specimens gave 37%. Obviously the
divergences between these figures are too slight to be dwelt upon, but
the fact that the atavists are as true or nearly as true inheritors of
the twisted race as the best selected individuals is clearly proved by
this experience.
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