MICROSCOPIC ORGANISMS IN INTESTINAL CANAL. 251 
fungoid origin of cholera! They consist of spherical or 
elliptical cells of various sizes, ranging from 3°5 to 9°2m in 
diameter, and frequently characterised by the brightly refractive 
oily appearance of their contents (Plate XVIII, figs. 20, 21). 
This latter character is not by any means an invariable one, how- 
ever, for in other cases they are finely clouded or molecular, and 
with more or less distinct vacuolation ; and the passage from the 
one condition to the other may readily be observed to take 
place specially under the influence of changes in the nature of 
the medium. They appear to consist of a very delicate mem- 
branous sac enclosing a mass of varying content-matter. They 
may either occur scattered singly through the basis or may be 
associated in groups, and, in the latter case, may sometimes be 
observed to be connected with one another by a delicate gela- 
tinous, intercellular basis, which, I take it, represents the struc- 
ture described by Hallier as the sporogenic cyst (Plate XVIII, 
fig. 20). As a rule, their occurrence is associated with that 
of zoospores and Amcebe, but in some excreta they are present 
apart from such bodies. The nnmber present in the excreta 
during health varies very considerably. In some cases of intes- 
tinal disorder they are present in increased numbers, but never 
apparently are they so very abundant as 7m certatn cases of cholera. 
In the normal excreta in health they are very transitory, dis- 
appearing like the zoospores very rapidly with the increasing 
acidity of the medium, so that specimens which when quite recent 
showed an abundance of them may, within the course of twenty- 
four hours, retain no traces of their presence. Like the zoo- 
spores, too, they are very susceptible to the influence of other 
changes in their surroundings, rapidly disappearing when they 
happened to be washed out into the ring of nutritive fluid 
surrounding the thicker portion of a preparation. Owing to 
their rapid disappearance from the unmixed excreta, it is hope- 
less to attempt their continuous investigation without the aid of 
suitable nutritive media; and of these, that which I have found 
to act most satisfactorily is the solution of cow dung which has 
been already mentioned as adapted to the requirements of the 
zoospores and Amcebee. Under the influence of this they may 
often be preserved for several days, and continued observations 
of various developmental changes occurring in them may thus 
be carried out. The results of such cultivations seem to me 
to have clearly shown that these enigmatic cells are reproductive 
bodies belonging to the Amcbe, and forming a connecting link 
between these and the zoospores, 
A suspicion that they really were products of reproductive 
processes occurring in the Amcebe was originally aroused by 
1 ¢Das Cholera Contagium,’ Leipzig, 1867. 
