In summer the range is
wider, and besides many trifoliolate leaves the curiously shaped
seven-bladed ones are not at all rare. In the fall and in the winter the
range of variability is narrowed, and at first sight the plants often
seem to bear only quinquefoliolate leaves.
[350] I have cultivated a new generation of this race nearly every year
since 1894, using always the strictest selection. This has led to a
uniform type, but has not been adequate to produce any further
improvement. Obviously the extreme limit, under the conditions of
climate and soil, has been reached. This extreme type is always
dependent upon repeated selection. No constant variety, in the older
sense, has been obtained, nor was any indication afforded that such a
type might ever be produced. On the contrary, it is manifest that the
new form belongs to the group of ever-sporting varieties. It is never
quite free from the old atavistic type of the trifoliolate leaves, and
invariably, when external conditions become less favorable, this
atavistic form is apt to gain dominion over the more refined varietal
character. Reversions always occur, both partial and individual.
Some instances of these reversions may now be given. They are not of
such a striking character as those of the snapdragon. Intermediate steps
are always occurring, both in the leaves themselves, and in the
percentages of deviating seedlings of the several parent plants.
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