none had reached the centre within this time. In this case there could
not be the least doubt that the chloroform had exerted an anaesthetic
influence on the leaves.
On the other hand, another plant was exposed under the same vessel for
a much longer time, viz. 20 m., to twice as much chloroform. Bits of
meat were then placed on the glands of many tentacles, and all of them,
with a single exception, reached the centre in from 13 m. to 14 m. In
this case, little or no anaesthetic effect had been produced; and how
to reconcile these discordant results, I know not.
Vapour of Sulphuric Ether. A plant was exposed for 30 m. to thirty
minims of this ether in a vessel holding 19 oz.; and bits of raw meat
were afterwards placed on many glands which had become pale-coloured;
but none of the tentacles moved. After 6 hrs. 30 m. the leaves appeared
sickly, and the discal glands were almost dry. By the next morning many
of the tentacles were dead, as were all those on which meat had been
placed; showing that matter had been absorbed from the meat which had
increased the evil effects of the vapour. After four days the plant
itself died. Another plant was exposed in the same vessel for 15 m. to
forty minims. One young, small, and tender leaf had all its tentacles
inflected, and seemed much injured. Bits of raw meat were placed on
several glands on two other and older leaves. These glands became dry
after 6 hrs.; and seemed injured; the tentacles never moved, excepting
one which was ultimately a little inflected. The glands of the other
tentacles continued to secrete, and appeared uninjured, but the whole
plant after three days became very sickly. [page 220]
In the two foregoing experiments the doses were evidently too large and
poisonous. With weaker doses, the anaesthetic effect was variable, as
in the case of chloroform. A plant was exposed for 5 m. to ten drops
under a 12-oz. vessel, and bits of meat were then placed on many
glands. None of the tentacles thus treated began to move in a decided
manner until 40 m. had elapsed; but then some of them moved very
quickly, so that two reached the centre after an additional interval of
only 10 m. In 2 hrs. 12 m. from the time when the meat was given, all
the tentacles reached the centre. Another plant, with two leaves, was
exposed in the same vessel for 5 m. to a rather larger dose of ether,
and bits of meat were placed on several glands. In this case one
tentacle on each leaf began to bend in 5 m.; and after 12 m. two
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