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Darwin, Charles, 1809-1882

"The Movements and Habits of Climbing Plants"

, but in one case in 3 hrs., all were
bent: they became straight again in about 4 hrs. afterwards. An
internode, which was rubbed as often as six or seven times, became
just perceptibly curved in 1 hr. 15 m., and in 3 hrs. the curvature
increased much; it became straight again in the course of the
succeeding night. I rubbed some internodes one day on one side, and
the next day either on the opposite side or at right angles to the
first side; and the curvature was always towards the rubbed side.
According to Palm (p. 63), the petioles of Linaria cirrhosa and, to a
limited degree, those of L. elatine have the power of clasping a
support.
SOLANACEAE.--Solanum jasminoides.--Some of the species in this large
genus are twiners; but the present species is a true leaf-climber. A
long, nearly upright shoot made four revolutions, moving against the
sun, very regularly at an average rate of 3 hrs. 26 m. The shoots,
however, sometimes stood still. It is considered a greenhouse plant;
but when kept there, the petioles took several days to clasp a stick:
in the hothouse a stick was clasped in 7 hrs. In the greenhouse a
petiole was not affected by a loop of string, suspended during
several days and weighing 2.


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