Before the above observations were made, some arched hypocotyls buried at
the depth of a quarter of an inch were uncovered; and in order to prevent
the two legs of the arch from beginning to separate at once, they were tied
together with fine silk. This was done partly because we wished to
ascertain how long the hypocotyl, in its arched condition, would continue
to move, and whether the movement when not masked and disturbed by the
straightening process, indicated circumnutation. Firstly a filament was
fixed to the basal leg of an arched hypocotyl close above the summit of the
radicle. The cotyledons were still partially enclosed within the
seed-coats. The movement was traced (Fig. 4) from 9.20 A.M. on Dec.
[page 15]
23rd to 6.45 A.M. on Dec. 25th. No doubt the natural movement was much
disturbed by the two legs having been tied together; but we see that it was
distinctly zigzag, first in one direction and then in an almost opposite
one. After 3 P.M. on the 24th the arched hypocotyl sometimes remained
stationary for a considerable time, and when moving, moved far slower than
before.
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