D. Keilin 
407 
well pronounced; the protoplasiu is transparent and the nucleus, which 
is still visible in the living parasite, contains a big karyosome. The 
protoplasm of the protomerit is less dense than that of the deutomerit 
and it contains some highly refractive corpuscles. 
The trophozoite, while still attached to the epithelial cell of the 
host, increases much in size till it reaches about 130-200/x in length 
(PL IX, figs. 3, 4, 5 and 6), then it separates from the epithelium, loosing 
the epimerit and is liberated in the lumen of intestine becoming a free 
living sporont. 
The full grown sporont is elongated, its maximum length is 300 g. 
and maximum width 85g (PI. IX, fig. 7); the protomerit is hemispherical. 
The protoplasm of the whole gregarine is very dense and dark and the 
nucleus is not visible when the parasite is alive. 
In forming the cyst two of these sporonts come together, simulating 
an association; they then fold over one against the other, uniting closely, 
and finally they become a spherical mass of a uniform grey colour. 
These early stages of the cyst formation are usually found in the 
intestine of the host (PI. IX, fig. 11). The further stages were found in the 
excrement of the larvae which I kept for many days (12-20) on moist 
blotting paper in a small wooden pill-box. 
