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another (figs. 28, 33, 35, 36) but in a few cases the nucleus and 
blepharoplast were apposed (figs. 30, 31, 31). On rare occasions the 
contents were slightly contracted from the varnish-like wall (figs. 
34-36). 
Division. 
(a) The Pre-flagellate. 
After the introduction of the parasite into a new host by way of the 
mouth, division occurs. As a result of repeated binary fission followed 
by growth, rosettes of pre-fiagellates (figs. 3, 5, 8) are fairly common. 
The sequence of events in nuclear division resembles that of the 
flagellate stage described below. The chromatophile area of the pre- 
flagellate, however, divides, generally symmetrically, and hence each 
new pre-flagellate is a replica of its parent. 
(6) Division of the Flagellate. 
Longitudinal division of (7. puZfas (figs. 18-22) is of two types:— 
(1) equal or symmetrical division ; (2) unequal or asymmetric fission. 
The processes have been observed in life and corroborated by reference 
to stained specimens. Division is initiated by the concentration of the 
substance of the blepharoplast into two masses, one at either end 
(fig. 18). The blepharoplast becomes bowed and presents a dumb¬ 
bell appearance (fig. 19). The two heads of the dumb-bell finally 
become separated (figs. 20, 21). Soon after division of the blepharo¬ 
plast has commenced, that of the nucleus begins, but the process is less 
rapid than is that of the blepharoplast. The flagellum and membrane 
next commence to split and as the flagellum violently lashes outwards, 
the division of the body follows. The two bodies thus formed gradually 
diverge (fig. 21) and a V-shaped oi’gauism then is seen. Ultimately 
the diverging arms of the V lie in a straight line (fig. 22) and the two 
daughter forms finally separate by constriction at the posterior end. 
In asymmetric division two types are encountered : 
(1) The blepharoplast and nucleus divide into unequal portions 
and the body fission follows that of the chromatic masses (fig. 22). 
(2) On rare occasions the nucleus and blepharoplast may divide 
symmetrically while the general protoplasm divides asymmetrically. 
Division is a rapid process and there is a great variety of forms 
resulting therefrom. I have not found division rosettes of the flagellate 
form of G. pulicis at all common. After the primary division, a second 
