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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

The same holds good for the crosses between spiny species and
their unarmed derivatives, as in the thorn-apple, the corn-crowfoot
(_Ranunculus arvensis_) and others.
Lack of starch in seeds is observed in some varieties of corn and of
peas. When such derivatives are crossed with ordinary starch-producing
types, the starch prevails in the hybrid.
It would take too much time to give further examples. But there is still
one point which should be insisted upon. It is not the systematic
relation of the two parents of a cross, that is decisive, but only the
occurrence of the same quality, in the one in an active, and in the
other in an inactive condition. Hence, whenever this relation occurs
between the parents of a cross, the active quality prevails in the
hybrid, even when the parents differ from each other in other respects
so as to be distinguished as systematic species. The white and red
campions give a red hybrid, the black and pale henbane (_Hyoscyamus
niger_ and _H. pallidus_) give a hybrid [284] with the purple veins and
center in the corolla of the former, the white and blue thornapple
produce a blue hybrid, and so on. Instances of this sort are common in
cultivated plants.
Having given this long list of examples of the rule of the dominancy of
the active character over the opposite dormant unit, the question
naturally arises as to how the antagonistic units are combined in the
hybrid.


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