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apparently represents four and a half
ellipses or ovals, with the longer axis of the first at nearly right angles
to that of the others. The longer axes of all were oblique to a line
joining the opposite cotyledons. The actual extreme distance from side to
side over which the summit of the tall hypocotyl passed in the course of 12
h. was .28 of an inch. The original figure was traced on a large scale, and
from the obliquity of the line of view the outer parts of the diagram are
much exaggerated.
Cotyledons.--On two occasions the movements of the cotyledons were traced
on a vertical glass, and as the ascending and descending lines did not
quite coincide, very narrow ellipses were formed; they therefore
circumnutated. Whilst young they rise vertically up at night, but their
tips always remain reflexed; on the following morning they sink down again.
With a seedling kept in complete darkness they moved in the same manner,
for they sank from 8.45 A.M. to 4.30 P.M.; they then began to rise and
remained close together until 10 P.M., when they were last observed.


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