NEW TYPE OF PPOTISTAN PAh'ASITE. 
447 
slinpe is typical of this phase of tlie parasite. The avernge 
size varies from 7-9^ /t in leng-tlp by 3^-5 in width; 
individuals with dimensions less than these occnr^ but larger 
ones are nearly always in the act of dividing ; the individual 
of fig. 48 is about the largest single oval found. 
In the case of the ovals, the minute structure can be made 
out satisfactorily only in wet-fixed preparations, stained by 
hmmatoxylin ; in Gfiernsa smears, the ovals — especially the 
large ones — stain much more intensely than the crescents, and 
usually appear rather blotchy, the stain being deposited to a 
greater extent either in, or immediately beneath, the 
(thicker) envelope. Hence, only two or three examples 
Text-figs. H-M. 
I- \ ■ . : 
H J K L M 
Ovals drawn either living or after fixation with osinic acid vapour. 
H, L and M show the envelope distinctly ; in J and K it is 
not visible. 
stained in this manner are figured, for the sake of compari- 
son (figs. 83-87). The ovals show two types of minute 
structure, which, at first sight, appear quire different; we 
think, however, that they are connected by intermediate con- 
ditions. The first type of structure is practically identical 
with that of many crescents. There is just the same differ- 
ence with regard to the distinctness of the envelope. In 
iminy individuals it stands off well from the general proto- 
plasm at the two ends of the body (figs, 39, 40, 53) ; in 
others, though these are fewer in number, it is not apparent 
at all (figs. 41, 43, 45, 54). The protoplasm stains in the 
same uniform manner and shows neither granules nor 
vacuoles. The chromatinic substance is distributed in the 
same characteristic manner, constituting usually a zone of 
