I then moved the stick to a
greater distance, so that it was struck by a point 2.5 inches from
the extremity of the penultimate internode; and it was then neatly
encircled by this part of the penultimate and by the ultimate
internode. After leaving the spirally wound shoot for eleven hours,
I quietly withdrew the stick, and in the course of the day the curled
portion straightened itself and recommenced revolving; but the lower
and not curled portion of the penultimate internode did not move, a
sort of hinge separating the moving and the motionless part of the
same internode. After a few days, however, I found that this lower
part had likewise recovered its revolving power. These several facts
show that the power of movement is not immediately lost in the
arrested portion of a revolving shoot; and that after being
temporarily lost it can be recovered. When a shoot has remained for
a considerable time round a support, it permanently retains its
spiral form even when the support is removed.
When a tall stick was placed so as to arrest the lower and rigid
internodes of the Ceropegia, at the distance at first of 15 and then
of 21 inches from the centre of revolution, the straight shoot slowly
and gradually slid up the stick, so as to become more and more highly
inclined, but did not pass over the summit.
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