C. M. Wen yon 
213 
Morphology of the Parasite as observed in Stained Preparations. 
In the stained films the flagellate now under consideration shows the 
same general characters as in the fresh specimens. In addition other 
details can be noted. At the anterior end of the body and a little to one 
side is a spherical vesicular nucleus. There is a definite nuclear mem¬ 
brane within which is an irregular network. One or more chromatin 
clumps are present and these are either situated at the centre of the 
nucleus or on the surface of the nuclear membrane. Near the nucleus 
is the insertion of the three flagella. These arise from a deeply staining 
chromatin granule. In some cases there appear to be two such granules 
from one of which arise two of the flagella, while from the other the 
remaining flagellum and possibly the marginal flagellum of the undulat¬ 
ing membrane takes origin. However the exact details of the connection 
of this marginal flagellum with the chromatin granules could not be 
very clearly seen. 
The protoplasm of the body is much vacuolated. Some of the 
vacuoles are food vacuoles and contain bacteria and other particles. 
The large cytostome with its two lips is very evident. The lips are most 
prominent at the middle of the cytostome and that of one side may over¬ 
lap that of the other. The undulating membrane within the cytostome 
is visible as a wavy line. Exactly where this line takes origin on the line 
of insertion of the undulating membrane was not very clear. The posi¬ 
tion of this line within the cytostome and the fact that it was never 
seen outside it seems to indicate an undulating membrane rather than 
a flagellum. The posterior end of the animal is most frequently drawn 
out to a fine point. In other cases it is blunt while in some of the 
smallest forms seen the body is spherical. In these small forms the 
cytostome could not be seen but the three anterior flagella were quite 
visible. Division forms were not seen unless those with the two 
chromatin granules near the nucleus are interpreted as early division 
forms. 
Encysted forms were encountered. These are oval bodies measuring 
7 p by 5'5 p. Within these cysts the characteristic nucleus, the large 
cytostome and some other details could be seen. It was impossible to 
decide whether these cysts were reproductive or merely protective. 
In addition to these undoubted cysts there occurred other bodies 
which appear to be derived from the flagellate. They are very similar 
Parasitology in 
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