Manito eBooks

M. March 21st to 9
A.M. 23rd. Seedling kept in darkness. Movement of bead magnified about 35
times.
[page 57]
and by this time the filament was attached some way down the little stem.
From some unknown cause, the hypocotyl moved far towards the left, but
there could be no doubt (Fig. 43) that it circumnutated. Another hypocotyl
was similarly observed, and it likewise moved in a strongly zigzag line to
the same side. This lateral movement was not caused by the attachment of
the glass filaments, nor by the action of light; for no light was allowed
to enter when each observation was made, except from vertically above.
The hypocotyl of a seedling was secured to a little stick; it bore nine in
appearance distinct cotyledons, arranged in a circle. The movements of two
nearly opposite ones were observed. The tip of one was painted white, with
a mark placed below, and the figure described (Fig. 44, A) shows that it
made an irregular
Fig. 44. Pinus pinaster: circumnutation of two opposite cotyledons, traced
on horizontal glass in darkness, from 8.45 A.


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