In one instance, an old tendril, which had nearly
ceased revolving, moved in one direction, whilst a young tendril
above moved in an opposite course. The two uppermost internodes
alone revolve; and as soon as the lower one grows old, only its upper
part continues to move. The ellipses or circles swept by the summits
of the internodes are about three inches in diameter; whilst those
swept by the tips of the tendrils, are from 15 to 16 inches in
diameter. During the revolving movement, the internodes become
successively curved to all points of the compass; in one part of
their course they are often inclined, together with the tendrils, at
about 45 degrees to the horizon, and in another part stand vertically
up. There was something in the appearance of the revolving
internodes which continually gave the false impression that their
movement was due to the weight of the long and spontaneously
revolving tendril; but, on cutting off the latter with sharp
scissors, the top of the shoot rose only a little, and went on
revolving. This false appearance is apparently due to the internodes
and tendrils all curving and moving harmoniously together.
A revolving tendril, though inclined during the greater part of its
course at an angle of about 45 degrees (in one case of only 37
degrees) above the horizon, stiffened and straightened itself from
tip to base in a certain part of its course, thus becoming nearly or
quite vertical.
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