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Scientific Memoirs by

were in the case of the dog into which they were introduced by inoculation, and
as, at all events, similar organisms have been shown by Dr. Lewis to occur in
the blood of healthy rats. It has further to be shown that they are invariably
present in cases of the disease. In so far as thermometrical data go, the
disease observed by Dr. Gunn at Meerut appears to have been identical with
that studied by Dr. Steel in Burma, and yet the presence of such organisms in
the blood was not apparently observed, and in so far as my own observations go
was not constant. This may, no doubt, possibly be due to the specimens of blood
having been taken at times when the organisms were absent or present in very
small numbers in the general circulation, as it is recorded that their appearance
is of an intermittent character, and, as regards the samples examined by me,
may possibly have been connected with the length of time elapsing between the
period at which they were taken and that at which they came into my posses-
sion. The facts are, however, at least such as to render it additionally neces-
sary that definite evidence should be forthcoming to show the constant
association of the disease with the presence of the parasites. The fact of the
occurrence of the disease in previously healthy animals and the appearance of
the parasite in their blood after inoculation do not afford data of any conclusive
value. They certainly show that the parasites can be transferred from the body
of one animal to that of another, but that is all. There is nothing to show that
they gave rise to the associated disease. No clean artificial cultivations have
as yet been carried out, and all inoculations have been conducted by means of
blood directly transferred from the diseased to the healthy animal; so that, fully
granting that the disease has been shown to be inoculable and that the parasites
are similarly transferable, there is yet nothing to show that the two phenomena
hold any beyond a parallel relation to one another; there is nothing to show that
the transplantation of the parasites was the cause of the development of the
disease in the inoculated animals. Whilst, on the one hand, there is this entire
absence of positive evidence of the pathogenic function of the parasites, there is,
on the other hand, some evidence pointing in an opposite direction—evidence
which is, at all events, calculated to raise additional doubts as to their essential
relation to the disease. This lies in Dr. Lewis' observations, which have been
already referred to, on the persistent intermittent occurrence of large numbers of
the organisms in the blood of a dog long after inoculation and quite apart from
the presence of any morbid symptoms.

II—On a peculiar, truly spirillar form of the Choleraic Comma-
Bacillus (Plate I, Fig. 2.)

     Truly spirillar forms of the choleraic comma-bacillus appear to occur with
extreme rarity in cultivations in Calcutta. It is, of course, far from uncommon
to meet with cultivations in which many of the elements are associated so
as to form wavy filaments of various lengths. These are, however, as a rule,