OBSERVATIONS ON HAMATOZOA IN CEYLON. 393 
following morning the parasites had all undergone dissolution 
after the manner of T'rypanosoma. 
The movements consist of slow gliding and turning, the 
“vermicule” sometimes actually doubling upon itself. Some- 
times it will become fixed by its attenuated hinder end, and 
will revolve by a slow screw-like motion after the manner of 
the spores of Sarcocystis. Then may ensue a rapid whirling 
of the body, causing a disturbance among the neighbouring 
corpuscles. 
Many films of the snake’s blood were prepared and stained, 
and in most of them we found that, besides the free parasites, 
many of the corpuscles contained bodies of relatively large 
size, more or less crescentic in shape. These endoglobular 
organisms were not at all like the ordinary hemogregarines, 
but consisted of a delicate protoplasmic membrane with red- 
stained granules surrounding a pale-blue stained central body 
with a densely staining nucleus. The discovery of various 
stages of development within certain narrow limits enabled 
us to recognise the enveloping body as the mother-cell of the 
contained body, and we accordingly described it as a cytocyst. 
The single organism or monozoite which the cytocyst pro- 
duces eventually escapes from the membrane and from the 
corpuscle, very much as a young Nemertine worm escapes 
from its pilidium, and becomes the free motile parasite de- 
scribed above. We find the monozoites at all stages of 
emergence, and it is probable that some of the rapid oscilla- 
tions of the parasite which were observed in the fresh prepara- 
tions represented violent efforts to free their hinder extremities 
from the corpuscles, 
The nucleus of the monozoite lies behind the centre of the 
body both before and after its birth. When fully formed 
within the cytocyst the hinder end of the monozoite is slightly 
bent, indicating that some pressure or tension is being exerted 
within. In the next stage the anterior end is found to have 
perforated the wall of the cytocyst, and the monozoite begins 
to push its way out through the opening thus produced. Here 
and there a corpuscle contains an empty cytocyst from which 
