It either followed the sun, or moved in an opposite course,
and sometimes stood still before reversing its direction. One oval
was completed in 3 hrs. 40 m.; of two horseshoe-shaped figures, one
was completed in 4 hrs. 35 m. and the other in 3 hrs. The shoots, in
their movements, reached points between four and five inches asunder.
The young leaves, when first developed, stand up nearly vertically;
but by the growth of the axis, and by the spontaneous bending down of
the terminal half of the leaf, they soon become much inclined, and
ultimately horizontal. The end of the leaf forms a narrow, ribbon-
like, thickened projection, which at first is nearly straight, but by
the time the leaf gets into an inclined position, the end bends
downwards into a well-formed hook. This hook is now strong and rigid
enough to catch any object, and, when caught, to anchor the plant and
stop the revolving movement. Its inner surface is sensitive, but not
in nearly so high a degree as that of the many before-described
petioles; for a loop of string, weighing 1.64 grain, produced no
effect. When the hook has caught a thin twig or even a rigid fibre,
the point may be perceived in from 1 hr.
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