428 
Eimeria n. sp. in Man 
ocysts were colourless, transparent, and spherical. Their diameter 
was between 40/x and 48/x, most of them measuring 45/x. The capsule was, 
as far as could be seen, composed of two layers, quite transparent; the inner 
one being the proper, homogeneous, well-defined wall, the outer appearing as 
an ill-defined mucous layer which was often difficult to detect. 
The whetstone-shaped spores had a length varying from 17-20/x and a 
breadth of 7-8 /x. The wall of the spore (sporocyst) was sharply defined except 
at certain spots on its outer surface where it appeared rough, possibly indi¬ 
cating the remains of a muCous outer layer. In general the ends of the spores 
were acute, but sometimes they were rather blunt. 
It was rather difficult to see the form of the sporozoites, as will be clear 
from the drawings. They seemed to be rather slender, one end being more 
obtuse than the other, and to have these obtuse ends directed towards 
opposite poles. I could not detect nuclei with certainty and the “crystal¬ 
line small bodies observed by Dobell (1919) in E. oxyspora seemed to be 
absent. 
Of an oocystic residual body only vestiges seemed sometimes present. On 
the contrary, however, sporocystic residua were quite evident in the form of 
one or two highly retractile spherical bodies of varying, but rather small, size. 
Sometimes the sporozoites had a “fixed,” coagulated appearance, with 
some bursts, suggesting necrosis and disintegration of their coagulated bodies. 
Suspended in a 2 per cent, eosin solution (with 0-9 per cent. NaCl) these 
forms readily stained red, confirming the fact that these sporozoites were 
dead already. 
Trying to obtain stained and durable preparations I met with difficulties, 
ith the Heidenhain stain (after moist fixation in the warm fluid of Schaudinn) 
I did not succeed in obtaining any differentiation. One saw only the outline 
of the oocysts and sometimes of the sporocvsts, but nothing of .their contents. 
In counterstaining with eosin, however, the bodies of the sporozoites stained 
red. But further details were not obtainable, at least not distinctly and con¬ 
stantly enough to rely on. 
As of course these oocysts puzzled me greatly, I afterwards made repeated 
examinations of this patient’s stools, but I never succeeded in finding them 
again. 
I may stipulate here that I have never found oocysts of this kind in other 
patients, although I have made between 1000 and 2000 stool examinations 
a year for a period of six years, nor have I ever seen them in animal faeces. 
The only coccidial parasites I frequently meet with are those of Eimeria 
stiedae in rabbits and Isospora bigemina in cats 1 . 
Trying to identify this Eimeria I consulted Dobell's critical and exhaustive 
epitome on coccidia parasitic in man (1919), and for a moment thought it 
I hey are quite like the European forms; only it struck me that the dimensions of the cysts 
of Eimeria stiedae are smaller (length 30 /a (25-35 /a), breadth 12-20 /a) than is generally admitted 
in Europe. 
