Experiment 3. A similar experiment to the last, with exactly the same
results.
Experiment 4. A fine leaf was placed in water at 100 (37 .7 Cent.),
which was then raised to 145 (62 .7 Cent.). Soon after immersion,
there was, as might have been expected, strong inflection. The leaf was
now removed and left in cold water; but from having been exposed to so
high a temperature, it never re-expanded.
Experiment 5. Leaf immersed at 130 (54 .4 Cent.), and the water raised
to 145 (62 .7 Cent.), there was no immediate inflection; it was then
placed in cold water, and after 1 hr. 20 m. some of the tentacles on
one side became inflected. This leaf was now placed in the strong
solution, and in 40 m. all the submarginal tentacles were well
inflected, and the glands blackened. After an additional interval of 2
hrs. 45 m. all the tentacles, except eight or ten, were closely
inflected, with their cells exhibiting a slight degree of aggregation;
but the spheres of protoplasm were very small, and the cells of the
exterior tentacles contained some pulpy or disintegrated brownish
matter.
Experiments 6 and 7. Two leaves were plunged in water at 135 (57 .2
Cent.) which was raised to 145 (62 .7 Cent.); neither became
inflected. One of these, however, after having been left for 31 m. in
cold water, exhibited some slight inflection, which increased after an
additional interval of 1 hr. 45 m., until
* Sachs states ( Traite de Botanique, 1874, p. 855) that the movements
of the protoplasm in the hairs of a Cucurbita ceased after they were
exposed for 1 m. in water to a temperature of 47 to 48 Cent., or 117
to 119 Fahr. [page 71]
all the tentacles, except sixteen or seventeen, were more or less
inflected; but the leaf was so much injured that it never re-expanded.
The other leaf, after having been left for half an hour in cold water,
was put into the strong solution, but no inflection ensued; the glands,
however, were blackened, and in some cells there was a little
aggregation, the spheres of protoplasm being extremely small; in other
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