cold water and kept in damp air, with bits of meat placed on their
discs. The leaf which had been exposed to the temperature of 110o
became in 15 m. greatly inflected; and in 2 hrs. every single tentacle
closely embraced the meat. So it was, but after rather longer
intervals, with the six other leaves. It appears, therefore, that the
warm bath had increased their sensitiveness when excited by meat.
I next observed the degree of inflection which leaves underwent within
stated periods, whilst still immersed in warm water, kept as nearly as
possible at the same temperature; but I will here and elsewhere give
only a few of the many trials made. A leaf was left for 10 m. in water
at 100 (37 .7 Cent.), but no inflection occurred. A second leaf,
however, treated in the same manner, had a few of its exterior
tentacles very slightly inflected in 6 m., and several irregularly but
not closely inflected in 10 m. A third leaf, kept in water at 105 to
106 (40 .5 to 41 .1 Cent.), was very moderately inflected in 6 m. A
fourth leaf, in water at 110 (43 .3 Cent.), was somewhat inflected in
4 m., and considerably so in from 6 to 7 m.
Three leaves were placed in water which was heated rather quickly, and
by the time the temperature rose to 115 -116 (46 .1 to 46 .06 Cent.),
all three were inflected. I then removed the lamp, and in a few minutes
every single tentacle was closely inflected. The protoplasm within the
cells was not killed, for it was seen to be in distinct movement; and
the leaves, having been left in cold water for 20 hrs., re-expanded.
Another leaf was immersed in water at 100o (37.7 Cent.), which was
raised to 120 (48 .8 Cent.); and all the tentacles, except the extreme
marginal ones, soon became closely inflected. The leaf was now placed
in cold water, and in 7 hrs. 30 m. it had partly, and in 10 hrs. fully,
re-expanded. On the following morning it was immersed in a weak
solution of carbonate of [page 69] ammonia, and the glands quickly
became black, with strongly marked aggregation in the tentacles,
showing that the protoplasm was alive, and that the glands had not lost
their power of absorption. Another leaf was placed in water at 110o
(43 .3 Cent.) which was raised to 120 (48 .8 Cent.); and every
tentacle, excepting one, was quickly and closely inflected. This leaf
was now immersed in a few drops of a strong solution of carbonate of
ammonia (one part to 109 of water); in 10 m. all the glands became
intensely black, and in 2 hrs. the protoplasm in the cells of the
pedicels was well aggregated. Another leaf was suddenly plunged, and as
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