15 m. to 1 hr. 13 m.
One large circle was swept at this latter unusually quick rate; but
generally the circles or ellipses were small, and sometimes the
course pursued was quite irregular. An internode, after making
several revolutions, sometimes stood still for 12 hrs. or 18 hrs.,
and then recommenced revolving. Such strongly marked interruptions
in the movements of the internodes I have observed in hardly any
other plant.
The leaves bear four leaflets, themselves subdivided, and terminate
in much-branched tendrils. The main petiole of the leaf, whilst
young, moves spontaneously, and follows nearly the same irregular
course and at about the same rate as the internodes. The movement to
and from the stem is the most conspicuous, and I have seen the chord
of a curved petiole which formed an angle of 59 degrees with the
stem, in an hour afterwards making an angle of 106 degrees. The two
opposite petioles do not move together, and one is sometimes so much
raised as to stand close to the stem, whilst the other is not far
from horizontal. The basal part of the petiole moves less than the
distal part. The tendrils, besides being carried by the moving
petioles and internodes, themselves move spontaneously; and the
opposite tendrils occasionally move in opposite directions.
Pages:
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142