E. P. Snijders 420 
was a specimen of his Eimeria oxyspora. A more thorough comparison, how¬ 
ever, showed many differences: 
1. The oocysts are larger in my case (45 /x as compared with 36 /x). 
2. The sporocysts are shorter (17-20 p as compared with 30-32 /x). 
3. The outer layer of the walls of oocyst and sporocyst is rather indistinct. 
4. The sporocystic residua are much more evident, and, on the contrary, 
an oocystic residuum seems to be almost absent. 
5. Dobell’s “crystalline” bodies between the nucleus and the posterior 
end of the sporozoites are absent. 
As for the cysts of Eimeria wenyoni, they also have a certain resemblance 
with the cysts here described; e.g. absence of oocystic residuum, absence of 
the “crystalline” bodies, presence of highly refractile sporocystic residua, 
relative smoothness of the outer surface of the sporocystic wall. But un¬ 
doubtedly the differences are more striking than the resemblances. Thus, in 
the first place, the cysts here described are more than twice as great in 
diameter (45/x as compared with 20 /x); secondly, the spores are more slender, 
being of tbe same breadth but nearly twice as long as those of Eimeria 
wenyoni ; thirdly, as a general rule, the ends of the sporocysts are acute and 
not obtuse; finally, the sporocystic residua are of a smaller size. 
Moreover, it may be noted that I found in my case some undifferentiated 
and incompletely differentiated oocysts in the stools, in contradistinction to 
the facts known of Eimeria wenyoni and E. oxyspora. But, with our present 
knowledge of this matter still being rather fragmentary, it is difficult to estimate 
the exact value of this difference. 
Concerning the other coccidial parasites in man (hepatic Eimeria and 
Isospora hominis) I think confusion is impossible. 
For all these reasons we are forced to accept the conclusion that the cysts 
in question belong to a species hitherto undescribed in human stools. 
I 
i.i. 
Now if we find unexpected things in the stools we always have to reckon 
with three possibilities, and I think it a great mistake to omit consideration 
of any of them: 
A. The stool is contaminated after its deposition. In our case I think this 
impossible, because the stool was passed into a dry, clean Petri dish; it was 
examined only half-an-hour later; and, above all, because we found the 
oocysts thoroughly mixed up with the faecal mass and not only at its surface. 
I have some reason for laying stress on this point, because I saw a 
case of a Javanese child wrongly diagnosed at the first examination as 
a case of Balantidiosis. This child was suffering from a severe attack of 
dysentery with bloody stools and high fever. In the stools the laboratory 
assistant found numerous protozoa, resembling Balantidium, many of 
which contained red blood-corpuscles, this being supposed an incontest¬ 
able sign of pathogenicity. So it was proclaimed as a case of Balantidiosis. 
28—2 
