FURTHER OBSERVATIONS ON C^ICAL PARASITES OF FOWLS. 63 
smears representing* a very faitliful picture of the actual 
state of infection. To the results obtained by this method 
we return in the second part of our paper. 
4. Chilomastix Gallinarum. 
As will be seen from the table of infected fowls in Part II 
of this paper, this clearly marked species is a relatively rare 
parasite ot' fowls, but in those individuals in which it occurs 
it is always abundant. 
For example, in No. 5, which is one of the chicks obtained 
from Llanfoist, the caeca! smears are one mass of Chilo- 
mastix gallinarum, which was, in fact, the only flagellate 
present, although neither of the other chicks which were 
obtained at Llanfoist at the same time showed any trace of 
the parasite. 
In addition to its well-marked morphological characteristics, 
Chilomastix gallinarum is sharply marked off from the 
other flagellates in the fowl by two features in its behaviour. 
In the first place, the division stages which are so common 
in the other flagellates, are, even in fowls well infected with 
this form, relatively rare. 
Secondly, the encystation stages, which in other flagellates 
are extraordinarily rare, are, in the case of Chilomastix, 
actually common. 
Chilomastix gallinarum can readily be recognised in 
live smears by its relatively large size, its spherical form, and 
large number of ingested bacteria. It moves on the warm 
stage fairly rapidly, in a rotary fashion. The body of the 
active Chilomastix is roughly spherical, though sometimes it 
is prolonged at the aboral end into a pointed tail. The body 
measures, roughly, on an average 9 /m by 7 ft, though larger 
and smaller forms are to be met with (PI. 10, figs. 1-4). 
From the anterior end of the body there are four fairly 
large flagella arising from a mass of darkly staining basal 
granules — the blepharoplast complex. It seems probable 
that there are four granules in all, and that each flagellum 
