Medical Officers of the Army of India.

9

varying degrees of acidity. Colonies of various kinds were developed in abun-
dance and in many cases presenting macroscopic features identical with those
of commatous origin. Specimens were prepared from all colonies which appeared
in any way to present distinctive features. The numbers of preparations from
individual plates in consequence amounted in some cases to as many as ten, but
in spite of this in not a single instance were commas of any kind to be detected.
The forms most commonly developed in the cultivations consisted of short
straight rods and micrococci, but in certain instances an abundant development
of elongated bacilli occurred, the colonies of which were of superficial habit with
peculiar lichenous, foliated margins. The variety of forms developed was
curiously limited in relation to the multifarious nature of those present in the
original materials. Cultivations were not, however, limited to primary plates, for
having become more and more convinced of the polymorphic nature of the
choleraic commas, and of the apparent relation which the appearance of special
forms bears to variations in the conditions in which cultivations are carried out—
the habit of growth acquired in one medium appearing to persist to a certain
extent for some time in others of different constitution—repeated cultivations of
materials derived from the primary plates were made on other plates and in
tubes. The number of successive cultivations made in this way in individual
instances was very considerable, in one case as many as seventeen successive
ones being carried out, but, in spite of continued subjection to conditions
favourable to the development of the commas associated with choleraic media, in
no instance did such development occur here. The nature of the substratum
and the course of cultivation were varied in different ways, the media being in
some cases solid, in others liquid, the reaction being varied, the primary cultiva-
tions being sometimes carried out in liquids, the original materials for inoculation
being sometimes employed whilst fresh, at others only after having been kept
for varying periods, but in all cases the result was alike, there was no develop-
ment of commas.

     These results would appear to indicate either that bodies of the nature of
the commas present in choleraic materials are entirely absent from normal
alvine evacuations whether in actual or potential condition, or that, if they be
present, that they are incapable of further development under conditions
favourable to those of choleraic origin. They also point out the absolute neces-
sity of cultivation experiments, showing, as they do, that the mere presence of
curved schizomycetes can neither determine their true nature, nor the character
of the medium in which they exist.

B.—On the occurrence of curved schizomycetes in the intestinal canal of
Guinea-pigs.

     Only one or two observations regarding this point were carried out. As has
been pointed out by Dr. Klein, curved schizomycete organisms form a character-

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