188 
Protozoa in Tipula 
young cyst a delicate envelope also of oval form, within which the cyst lies 
excentrically. This is the jieriplast of the flagellate, within which the 
cytoplasm has contracted, surrounding itself with the true cyst membrane. 
This outer envelope disintegrates and disappears from the older cysts. 
Fig. 26 shows small oval flagellates (3'5 ya x 2‘5 /i) probably just emerged 
from the cysts. I have never seen more than one flagellum in these 
small forms. 
Fig. 27. E. alexeieffl. Stage in division. 
I have observed a few division-stages of E. alexeieffi. (Fig. 27), 
which agree with the figures of Robertson and Martin (1911) for the 
division of Chiloniastix gallinarum. 
I have recently had the opportunity of making a comparison between 
the embadomonads of Tipula and the species of Ghilomastix described 
by Alexeieff. I am now persuaded of the close relationship between 
the two genera, to which Fanapepea Prowazek (1911) is probably also 
relatedh 
III. Bacteria. 
Bacteria occur in enormous quantities. Chief among them is a 
large sinuous form resembling Bacillus jiexilis Dobell. 
^ A further diagnosis of the genus Emhadornonas is necessitated by the details of 
structure revealed in the large form E. alexeieffi: but I prefer to hold this over until 
I have worked out the life-cycle more fully. 
