The seedlings from the reciprocal cross, that is, from the crimson-green
variety fertilised with pollen from the white-green variety, offer a
somewhat more curious case. A few of these crossed seedlings reverted to
a pure green variety with their leaves less cut and curled, so that they
were altogether in a much more natural state, and these plants grew more
vigorously and taller than any of the others. Now it is a strange fact
that a much larger number of the self-fertilised seedlings from the
crimson-green variety than of the crossed seedlings thus reverted; and
as a consequence the self-fertilised seedlings grew taller by 2 1/2
inches on an average than the crossed seedlings, with which they were
put into competition. At first, however, the crossed seedlings exceeded
the self-fertilised by an average of a quarter of an inch. We thus see
that reversion to a more natural condition acted more powerfully in
favouring the ultimate growth of these plants than did a cross; but it
should be remembered that the cross was with a semi-sterile variety
having a feeble constitution.
Iberis umbellata.
VAR. KERMESIANA.
This variety produced plenty of spontaneously self-fertilised seed under
a net. Other plants in pots in the greenhouse were left uncovered, and
as I saw small flies visiting the flowers, it seemed probable that they
would be intercrossed. Consequently seeds supposed to have been thus
crossed and spontaneously self-fertilised seeds were sown on opposite
sides of a pot.
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