388 The Philippine Journal of Science 1920 
were seen to have been ingested (Plate 1, figs. 4 and 13). In 
none of the specimens were any chromidia blocks seen — a char- 
acter commonly found in examining specimens of Entamoeba 
histolytica. 
In order to exclude any source of error due to faulty technic, 
I had recourse to the following procedure : I made several prep- 
arations from different samples of dysenteric stools and passed 
them through the same fixing and staining processes as the prep- 
arations under consideration. On examining the former I had 
not the slightest difficulty in recognizing the clear, circular his- 
tolytica nucleus. Furthermore, in bringing out the distinctive 
points in the characters of this amoeba and those of Entamoeba 
histolytica I had, for comparison, some permanently mounted 
specimens from the pus of a case of liver abscess in which there 
were abundant amoebse, each field showing fifteen to twenty in- 
dividuals. The nuclei in these showed all the possible variations 
described by various authors as cyclic changes. No extreme va- 
riation in the shape of the nucleus of Entamoeba histolytica is 
comparable to the nucleus of this amoeba. 
STUDY OF SECTIONED MATERIAL 
As noted before, I made sections through the affected por- 
tions of the small and large intestines. These were hardened 
in alcohol and then embedded in paraffin. The sections were 
stained in the same way as the smears. A few were stained by 
Ehrlich’s hsematoxylin, but as these failed to differentiate the 
amoebse, this method was given up. 
I sectioned through two portions of the small intestine (Plate 
2, fig. 2, and Plate 3), one in which there was an ulcer and 
another in which there was no discontinuity of the mucous mem- 
brane. In both, the peritoneal surface showed the lesion seen 
in fresh material by the unaided eye. I shall describe the peri- 
toneal lesion first as great interest attaches to it. I am not 
aware of any inflammation of the peritoneum that can be attri- 
buted to amoebse. Moreover, this amoebic peritonitis, if I may 
be allowed to coin the term, differs entirely from ordinary peri- 
tonitis and is, therefore, a distinct pathological entity. This 
lesion, which was caused by the amoebse, showed, when the ma- 
terial was fresh, a distinct red elevated patch, in the scrapings 
from which I found numerous amoebse. When a stained section 
of this portion of the small intestine was studied under a low 
power this patch was noticed to be stained distinctly less faintly 
than the rest of the tissue (Plate 3, a). The thickness of the 
patch, as will be seen, nearly equals the combined thickness of 
