240 
original nucleus persists as a homogeneous lightly staining mass, 
which retains its original form and moves to one side of the parasite. 
At this stage usually one long flagellum arises in fhe neighbourhood 
of a small chromatic body very often situated at one end of the 
parasite (figs. 61-64), Shortly after, a second flagellum is formed, 
sometimes arising in close vicinity to the origin of the first flagellum, 
sometimes at some distance (fig. 65). 
The above described development is very liable to modifications. 
Occasionally two large masses nf chromatin are thrown out of the 
nucleus (fig. 68), and at the same time these latter sometimes divide 
(fig. 71). 
Whilst these nuclear changes are taking place, the parasita 
increase in size, and become elongated. The protoplasm changes its 
appearance, and becomes very loose and vacuolated. The dimensions 
of fully developed flagellate forms vary between 6 to 8 in length 
and 2 to 3 in width. 
These forms have been repeatedly observed by us in very small 
numbers in the peripheral blood of dogs on the day before death. 
Only in one animal were they abundant, and only in this case have 
we been able to follow their development. The blood was taken in 
the morning of the day before death. Films made actually on the 
day of death did not show any of these forms, neither in the peripheral 
nor in the heart blood, only two of these flagellated cells being iomd 
m organ films (spleen and bone-marrow). 
This observation seems to point to the fact that the biflagellate 
forms of Piroplasma cants represent a very transient stage in its Hfe- 
Instory, For this reason, it might have been very easily overlooked 
e, however, at present, are not able to form a definite opinion as to 
the Significance of this stage in the life-history of the parasite, 
especially as the subsequent development of the flagellate forms could 
not be traced 
Up to the present, no observations, either in culture or in the 
intermediate host, throw any light upon their meaning. Develop¬ 
mental stages of these flagellate forms in some respects resemble 
those occurring in the development of the flagellate forms in the 
cultures of Leishmania donovani. 
