glands were as black as ever. Half-minims were placed on the discs of
six leaves, and no inflection ensued; but after three days the glands
on the discs appeared rather dry, yet to my surprise were not
blackened. On another occasion drops were placed on the discs of six
leaves, and a considerable amount of inflection was soon caused; but as
I had not filtered the solution, floating particles may have acted on
the glands. After 24 hrs. bits of meat were placed on the discs of
three of these leaves, and next day they became strongly inflected. As
I at first thought that the poison might not have been dissolved in
pure water, one grain was added to 437 grains of a mixture of one part
of alcohol to seven of water, and half-minims were placed on the discs
of six leaves. These were not at all affected, and when after a day
bits of meat were given them, they were slightly inflected in 5 hrs.,
and closely after 24 hrs. It follows from these several facts that a
solution of curare induces a very moderate degree of inflection, and
this may perhaps be due to the presence of a minute quantity of
albumen. It certainly is not poisonous. The protoplasm in one of the
leaves, which had been immersed for 24 hrs., and which had become
slightly inflected, had undergone a very slight amount of
aggregation not more than often ensues from an immersion of this length
of time in water.
Acetate of Morphia. I tried a great number of experiments with this
substance, but with no certain result. A considerable number of leaves
were immersed from between 2 hrs. and 6 hrs. in a solution of one part
to 218 of water, and did not become inflected. Nor were they poisoned;
for when they were washed and placed in weak solutions of phosphate and
carbonate of ammonia, they soon became strongly inflected, with the
protoplasm in the cells well aggregated. If, however, whilst the leaves
were immersed in the morphia, phosphate of ammonia was added,
inflection did not rapidly ensue. Minute drops of the solution were
applied in the usual manner to the secretion round between thirty and
forty glands; and when, after an interval of 6 m:, bits of meat, a
little saliva, or particles of glass, were placed on them, the movement
of the tentacles was greatly retarded. But on other occasions no such
retardation occurred. Drops of water similarly applied never have any
retarding power. Minute drops of a solution of sugar of the same
strength (one part to 218 of water) sometimes retarded the subsequent
action of meat and of particles of glass, and [page 206] sometimes did
not do so. At one time I felt convinced that morphia acted as a
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