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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

There is an average of between 50 and 100,
constituting a nearly filled crown around the central capsule. Around
this average the smaller deviations are most numerous and the larger
ones more rare. The inspection of any bed of the variety suffices to
show that, taken broadly, the ordinary laws of fluctuating variability
are applicable. No counting of the single individuals is required to
dispel all doubts on this point.
Moreover all intermediate steps respecting the conversion of the single
stamens may nearly always be seen. Rarely all are changed into normal
secondary ovaries with a stigma and with a cavity filled with ovules.
Often the stigma is incomplete or even almost wanting, in other
instances the ovules are lacking or the cavity itself is only partially
developed. Not rarely some stamens are reduced and converted into thin
hard stalks, without any appearance of an ovary at their tip. But then
the demarcation [376] between them and the thalamus fails, so that they
cannot be thrown off when the flower fades away, but remain as small
stumps around the base of the more fully converted filaments. This fact
would frequently render the enumeration of the altered organs quite
unreliable.
For these reasons I have chosen a group of arbitrary stages in order to
express the degree of deviation for a given lot of plants.


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