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"The Power of Movement in Plants"

10 A.M. on the 12th, but was
interrupted by some small oscillations and zigzags, showing movement in
different directions. After 11.10 A.M. on the 12th this part of the stem,
still considerably curved, circumnutated in a conspicuous manner until
nearly 3 P.M. on the 13th; but during all this time a downward movement of
the filament prevailed, caused by the continued straightening of the stem.
By the afternoon of the 13th, the summit, which had originally been
deflected more than a right angle from the perpendicular, had grown so
nearly straight that the tracing could no longer be continued on the
vertical glass. There can therefore be no doubt that the straightening of
the abruptly curved portion of the growing stem of this plant, which
appears to be wholly due to hyponasty, is the result of modified
circumnutation. We will only add that a filament was fixed in a different
manner across the curved summit of another plant, and the same general kind
of movement was observed.
Trifolium repens.--In many, but not in all the species of Trifolium, as the
separate little flowers wither, the sub-peduncles bend downwards, so as to
depend parallel to the upper part of the main peduncle.


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