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ducing definite lesions in monkeys by feeding them with cultures of amœbæ, points
out that dysenteric symptoms are not rare amongst monkeys, and adds that
the bloody mucus, being a medium rich in red blood corpuscles and serous fluid,
the amœbæ normally present develop in it. He is inclined to consider that the
true cause of the dysentery in monkeys is not amœbic. In conclusion he asks the
question, whether in the investigation of Musgrave and Clegg there was a true
primary amœbic infection in monkeys at all. As we have already pointed out,
amœbæ resembling those cultured from dysenteric stools of man can be cultivated
from normal monkeys, and further, that these animals suffer from symptoms
of dysentery which in some cases end fatally.

     Hence in using monkeys for the production of experimental amœbic dysentery
it is necessary to be aware of this fact, otherwise erroneous conclusions may be
arrived at. We have carried out a number of feeding experiments in monkeys with
cultures of amœbæ; details of some of these are given below. We have not been
able to convince ourselves that we have induced a true amœbic dysentery in
monkeys, and in this respect we are in agreement with Noc. Some of the animals
have died with ulceration of the large intestine, which may have been of amœbic
origin, but the fact that uninfected monkeys with amœbæ in their stools may die
and show alterations in the large intestine renders the experimental results difficult
of interpretation. From what has been said above it will be readily understood
how complicated the whole subject is, rendering conclusive experimental proof of
the pathogenicity of different species of amœba very difficult. In this connection,
however, the quotation from Doflein's work (p. 8 of this Report) is of interest.

    The following is an account of some of the feeding experiments carried out on
monkeys :—

Ex. 7.—MONKEY.

    The strain of amœba used in this experiment was cultivated from the stools
of a case of dysentery No. 8250 Private A, on May 10, 1909.

    May 13th, 1909.—Two small petri plates of this strain, which showed many
cysts, were emulsified with 0.75 NaCl, which had been rendered distinctly alkaline ;
each 100 c.c. contained 1 c.c. normal NaoH. This emulsion was introduced into
the stomach of this monkey by means of a catheter. Weight of monkey 3,200
grams.

    June 29th, 1909.—Two small plates 14th and 15th passage emulsified and
given as before.

    July 19th, 1909.—An emulsion of two plates 20th and 21st passage of the
same strain of amœba showing many cysts was made in the same way and intro-
duced into the stomach of this monkey.

    August 2nd.—Since July 28th this monkey has had frequent small stools of
bloed and mucus: died this morning. Post mortem.—Weight 2,760 grams. On