tentacles on one leaf, and one on the second leaf, reached the centre.
In 30 m. after the meat had been given, all the tentacles, both those
with and without meat, were closely inflected; so that the ether
apparently had stimulated these leaves, causing all the tentacles to
bend.
Vapour of Nitric Ether. This vapour seems more injurious than that of
sulphuric ether. A plant was exposed for 5 m. in a 12-oz. vessel to
eight drops in a watch-glass, and I distinctly saw a few tentacles
curling inwards before the glass was removed. Immediately afterwards
bits of meat were placed on three glands, but no movement ensued in the
course of 18 m. The same plant was placed again under the same vessel
for 16 m. with ten drops of the ether. None of the tentacles moved, and
next morning those with the meat were still in the same position. After
48 hrs. one leaf seemed healthy, but the others were much injured.
Another plant, having two good leaves, was exposed for 6 m. under a
19-oz. vessel to the vapour from ten minims of the ether, and bits of
meat were then placed on the glands of many tentacles on both leaves.
After 36 m. several of them on one leaf became inflected, and after 1
hr. almost all the tentacles, those with and without meat, nearly
reached the centre. On the other leaf the glands began to dry in 1 hr.
40 m., and after several hours not a single tentacle was inflected; but
by the next morning, after 21 hrs., many were inflected, though they
seemed much injured. In this and the previous experiment, it is
doubtful, owing to the injury which the leaves had suffered, whether
any anaesthetic effect had been produced.
A third plant, having two good leaves, was exposed for only 4 m. in the
19-oz. vessel to the vapour from six drops. Bits of meat were then
placed on the glands of seven tentacles on the [page 221] same leaf. A
single tentacle moved after 1 hr. 23 m.; after 2 hrs. 3 m. several were
inflected; and after 3 hrs. 3 m. all the seven tentacles with meat were
well inflected. From the slowness of these movements it is clear that
this leaf had been rendered insensible for a time to the action of the
meat. A second leaf was rather differently affected; bits of meat were
placed on the glands of five tentacles, three of which were slightly
inflected in 28 m.; after 1 hr. 21 m. one reached the centre, but the
other two were still only slightly inflected; after 3 hrs. they were
much more inflected; but even after 5 hrs. 16 m. all five had not
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