30 m.; and, as the day became warmer, a
second circle was completed in 4 hrs. 10 m. The shoots sometimes
make a whole or a half spire round a vertical stick, they then run
straight up for a space, and afterwards turn spirally in an opposite
direction. The petioles of very young leaves about one-tenth of
their full size, are highly sensitive, and bend towards the side
which is touched; but they do not move quickly. One was perceptibly
curved in 1 hr. 10 m., after being lightly rubbed, and became
considerably curved in 5 hrs. 40 m.; some others were scarcely curved
in 5 hrs. 30 m., but distinctly so in 6 hrs. 30 m. A curvature was
perceptible in one petiole in between 4 hrs. 30 m. and 5 hrs., after
the suspension of a little loop of string. A loop of fine cotton
thread, weighing one sixteenth of a grain (4.05 mg.), not only caused
a petiole slowly to bend, but was ultimately so firmly clasped that
it could be withdrawn only by some little force. The petioles, when
coming into contact with a stick, take either a complete or half a
turn round it, and ultimately increase much in thickness. They do
not possess the power of spontaneously revolving.
Lophospermum scandens, var.
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