In order to satisfy myself on these points, I made some
pedigree-cultures with the striped forms of dame's violet (_Hesperis
matronalis_) [324] and of _Clarkia pulchella_. Both of them are
ever-sporting varieties. The experiments were conducted during five
generations with the violet, and during four with the striped Clarkia,
including the progeny of the striped and of the monochromatic red
offspring of a primitive striped plant. I need not give the figures here
for the numerical relations between the different types of each group,
and shall limit myself to the statement that they behaved in exactly the
same manner as the snapdragon.
It is worth while to dwell a moment on the capacity of the individuals
with red flowers to reproduce the striped type among their offspring.
For it is manifest that this latter quality must have lain dormant in
them during their whole life. Darwin has already pointed out that when a
character of a grandparent, which is wanting in the progeny, reappears
in the second generation, this quality must always be assumed to have
been present though latent in the intermediate generation. To the many
instances given by him of such alternative inheritance, the
monochromatic reversionists of the striped varieties are to be added as
a new type. It is moreover, a very suggestive type, since the latency is
manifestly of quite another character than for instance in the case of
Mendelian hybrids, and probably more allied to those instances, [325]
where secondary sexual marks, which are as a rule only evolved by one
sex, are transferred to the offspring through the other.
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