As in the last chapter, I will first give my experiments, and then a
brief summary of the results with some concluding remarks.
[Acetate of Strychnine. Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves; so that each received
1/960 of a grain, or .0675 mg. In 2 hrs. 30 m. the outer tentacles on
some of them were inflected, but in an irregular manner, sometimes only
on one side of the leaf. The next morning, after 22 hrs. 30 m. the
inflection had not increased. The glands on the central disc were
blackened, and had ceased secreting. After an additional 24 hrs. all
the central glands seemed dead, but the inflected tentacles had
re-expanded and appeared quite healthy. Hence the poisonous action of
strychnine seems confined to the glands which have absorbed it;
nevertheless, these glands transmit a motor impulse to the exterior
tentacles. Minute drops (about 1/20 of a minim) of the same solution
applied to the glands of the outer tentacles occasionally caused them
to bend. The poison does not seem to act quickly, for having applied to
several glands similar drops of a rather stronger solution, of one part
to 292 of water, this did not prevent the tentacles bending, when their
glands [page 200] were excited, after an interval of a quarter to three
quarters of an hour, by being rubbed or given bits of meat. Similar
drops of a solution of one part to 218 of water (2 grs. to 1 oz.)
quickly blackened the glands; some few tentacles thus treated moved,
whilst others did not. The latter, however, on being subsequently
moistened with saliva or given bits of meat, became incurved, though
with extreme slowness; and this shows that they had been injured.
Stronger solutions (but the strength was not ascertained) sometimes
arrested all power of movement very quickly; thus bits of meat were
placed on the glands of several exterior tentacles, and as soon as they
began to move, minute drops of the strong solution were added. They
continued for a short time to go on bending, and then suddenly stood
still; other tentacles on the same leaves, with meat on their glands,
but not wetted with the strychnine, continued to bend and soon reached
the centre of the leaf.
Citrate of Strychnine. Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves; after 24 hrs. the outer
tentacles showed only a trace of inflection. Bits of meat were then
placed on three of these leaves, but in 24 hrs. only slight and
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