Medical Officers of the Army of India.
17
served to confirm the belief in polymorphism as a character of the choleraic co
m - m a s u n d e r t h e i n f l u e n c e o f v a r y i n g c o n d i t i o n s . T h e r e c a n b e n o q u e s t i o n
regarding the correctness of Dr. Klein's observation relative to the occurrence of
processes of multiplication by division of a type differing from the ordinarily re-
cognised transverse one. In some cases the processes are of distinctly longi-
tudinal type and the long axes of the resulting commas then follow the same
direction as that of the parent body, where this is of elongated form. I am
strongly inclined to believe that processes of this character are not peculiar to
the choleraic commas, but will be found to occur in the case of other schizo-
mycete organisms. In a preparation of large oval cocci, developed in a cultiva-
tion of materials from a diphtheritic patch on the surface of a wound in a case of
erysipelas, which is now in my possession, there are, I believe, clear evidences of
the occurrence of similar processes of longitudinal division.
In other cases the process of division is primarily transverse, but at the
same time differs from the commonly recognised process in details and results.
In them we have transverse division of the protoplasm as the result of extensive
vacuolation, and the development of the resultant commas is such that their
long axes are transverse to that of the parent.
These processes of multiplication of commas are initiated by processes of
vacuolation leading to gradual sub-division of the originally continuous protoplasm,
and such vacuolation only occurs under certain circumstances. It tends to
appear, according to Dr. Klein's observations, in association with depression of
t e mp e r a t u r e ; a n d , s o f a r a s I h a v e b e e n a b l e t o a s c e r t a i n , i t i s a l s o a s s o c i a t e d
with partial exhaustion or acidity of the substratum. In recently started alkaline
or neutral cultivations conducted at a temperature of a certain degree of eleva-
tion, such processes of vacuolation and division do not occur, and continuous
processes of transverse division of the ordinarily recognised type lead to the
accumulation of typical commas. Where processes of vacuolative division have
been established, they may be caused to disappear by cultivation under the
conditions favouring the ordinary processes of multiplication. This result, how-
ever, does not necessarily occur completely at once. A varying number of suc-
cessive cultivations may have to be carried out ere these abnormal forms and
processes are completely replaced by the typical ones. It would appear that
we have here indications of the establishment of a special habit of growth in
connection with certain conditions and tending to be propagated hereditarily for
some time under other circumstances.
On the other hand if successive generations of the organism are continu-
ously exposed to the influence of the conditions favouring the abnormal process-
es an opposite result ensues. There is a progressive tendency to disappearance
of the typical forms and to the substitution of abnormal ones differing more and
more from the original type. Taking a material consisting of typical commas as
the primary source of a series of successive cultivations, we obtain various results
3