M. to 8.35 P.M. Nov. 25th.
Movement of tip in A magnified about 22 times, here reduced to one-half of
original scale.
circle in the course of about 8 h. during the night it travelled to a
considerable distance in the direction indicated by the broken line. A
glass filament was attached longitudinally to the other cotyledon, and this
nearly completed (Fig, 44, B) an irregular circular figure in about 12
hours. During the night it also moved to a considerable distance, in the
direction indicated by the broken line. The cotyledons therefore
circumnutate independently of the movement of the hypocotyl. Although they
moved much during the night, they did not approach each other so as to
stand more vertically than during the day.
[page 58]
Cycas pectinata (Cycadeae).--The large seeds of this plant in germinating
first protrude a single leaf, which breaks through the ground with the
petiole bowed into an arch and with the leaflets involuted. A leaf in this
condition, which at the close of our observations was 2 ? inches in height,
had its movements traced in a warm greenhouse by means of a glass filament
bearing paper triangles attached across its tip.
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