Some flowers of this race are striped, others are not. On a hasty survey
there seem to be three types, pure yellow, pure red, and stripes [316]
with all their intermediate links of narrower and broader, fewer and
more numerous streaks. But on a close inspection one does not succeed in
finding pure yellow racemes. Little lines of red may be found on nearly
every flower. They are the extreme type on this side of the range of
variability. From them an almost endless range of patterns passes over
to the broadest stripes and even to whole sections of a pure red. But
then, between these and the wholly red flowers we observe a gap, which
may be narrower by the choice of numerous broad striped individuals, but
which is never wholly filled up. Hence we see that the red flowers are a
separate type within the striped variety.
This red type springs yearly from the striped form, and yearly reverts
to it. This is what in the usual descriptions of this snapdragon, is
called its sporting. The breadth of the streaks is considered to be an
ordinary case of variability, but the red flowers appear suddenly,
without the expected links. Therefore they are to be considered as
sports. Similarly the red forms may suddenly produce striped ones, and
this too is to be taken as a sport, according to the usual conception of
the word.
Such sports may occur in different ways. Either by seeds, or by buds, or
even within the single spikes. Both opposite reversions, [317] from
striped to red and from red to stripes, occur by seed, even by the
strictest exclusion of cross-fertilization. As far as my experiments go,
they are the rule, and parent-plants that do not give such reversions,
at least in some of their offspring, are very rare, if not wholly
wanting. Bud-variations and variations within the spike I have as yet
only observed on the striped individuals, and never on the red ones,
though I am confident that they might appear in larger series of
experiments. Both cases are more common on individuals with broad
stripes than on plants bearing only the narrower red lines, as might be
expected, but even on the almost purely yellow individuals they may be
seen from time to time. Bud-variations produce branches with spikes of
uniform red flowers. Every bud of the plant seems to have equal chances
to be transformed in this way. Some striped racemes bear a few red
flowers, which ordinarily are inserted on one side of the spike only. As
they often cover a sharply defined section of the raceme, this
circumstance has given rise to the term of sectional variability to
cover such cases. Sometimes the section is demarcated on the axis of the
flower-spike by a brownish or reddish color, sharply contrasting with
the green hue of the remaining parts. Sectional variation may be looked
at as a [318] special type of bud-variation, and from this point of view
we may simplify our inquiry and limit ourselves to the inheritance of
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