4 hrs. 15 m. the outer tentacles were much inflected; and after 6 hrs.
30 m. those on two of the leaves were closely inflected and the blade
of one; the third leaf was only moderately affected. The leaves
remained in the same state during the next day, but after 48 hrs.
re-expanded.
Three leaves were now immersed, each in thirty minims of the solution,
so that each received 1/16 of a grain, or 4.048 mg. In 6 m. there was
some inflection, which steadily increased, so that after 2 hrs. 30 m.
all three leaves were closely inflected; the glands were at first
somewhat darkened, then rendered pale; and the protoplasm within the
cells of the tentacles was partially aggregated. The little masses of
protoplasm were examined after 3 hrs., and again after 7 hrs., and on
no other occasion have I seen them undergoing such rapid changes of
form. After 8 hrs. 30 m. the glands had become quite white; they had
not secreted any great quantity of mucus. The leaves were now placed in
water, and after 40 hrs. re-expanded, showing that they were not much
or at all injured. During their immersion in water the protoplasm
within the cells of the tentacles was occasionally examined, and always
found in strong movement.
Two leaves were next immersed, each in thirty minims of a much stronger
solution, of one part to 109 of water; so that each received 1/4 of a
grain, or 16.2 mg; After 1 hr. 45 m. the sub-marginal tentacles were
strongly inflected, with the glands somewhat pale; after 3 hrs. 30 m.
both leaves had all their tentacles closely inflected and the glands
white. Hence the weaker solution, as in so many other cases, induced
more rapid inflection than the stronger one; but the glands were sooner
rendered white by the latter. After an immersion of 24 hrs. some of the
tentacles were examined, and the protoplasm, still of a fine purple
colour, was found aggregated into chains of small globular masses.
These changed their shapes with remarkable quickness. After an
immersion of 48 hrs. they were again examined, and their movements were
so plain that they could easily be seen under a weak power. The leaves
were now placed in water, and after 24 hrs. (i.e. 72 hrs. from their
first immersion) the little masses of protoplasm, which had become of a
dingy purple, were still in strong movement, changing their shapes,
coalescing, and again separating.
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