STUDIES ON CEYLON H#MATOZOA. 687 
‘hese small forms have hyaline protoplasm staining faintly 
with the blue of the Romanowsky combination. ‘The proto- 
plasmic halo is not visible in these forms, and in the wet 
preparation the membrane or outer ring is always rather 
faint. 
The kinetonucleus lies very close to the anterior end of the 
body which tapers very rapidly to a sharp point. The mem- 
brane is relatively wide and the free flagellum is long. 
Division stages in the adult Trypanosome must be exceed- 
ingly rare, as although a very large number of well-infected 
films have been searched | have never come across any of the 
full-grown forms in this condition. Among the forms inter- 
mediate between the adult and the small specimens, however, 
individuals with two nuclei and dividing kinetonuclei are to 
be found; they are never numerous, and I can say nothing 
of the details of the process (Pl. 16, fig. 7). 
As already indicated I can find no morphological grounds 
for dividing the adult organism as found in the blood of the 
tortoise into male, female, and indifferent. There is no 
evidence to suggest that the small specimens like those shown 
in Pl. 16, figs. 5 and 6,are males and the large females, and 
outside of this the difference among the specimens is very 
slight, and involves apparently only protoplasmic features. 
This, in itself, is, however, no argument against an ultimate 
sexual differentiation or conjugation in the intermediate host. 
The material from the leeches, | am sorry to say, was 
mostly fixed by the dry method followed by alcohol, a good 
deal being fixed by the osmic vapour method to act as a 
control. ‘he Trypanosome is also to be recognised on sec- 
tions of the whole leech, but it is difficult to get a very clear 
and brilliant picture. However, the dry method is better 
adapted to the thin leaf-like shape of the 'T'rypanosome in the 
intermediate host. 
The detail of the very earliest changes in the T'rypano- 
some upon being taken into the leech is difficult to get in 
the stained preparations as they occur before the leech has 
ceased feeding. However, they are sufficiently clear from 
