STUDIES ON PARASITIC PROTOZOA. 
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previous observers. The axostyle arises from the neighbour- 
hood of the basal granules, passes down one side of the 
nucleus and pursues a curved course for some distance below; 
it seldom extends into the posterior third of the body, and is 
often completely absent. 
The feeble development of the axostyle is no doubt asso- 
ciated with the presence of the rigid pellicula, which makes 
internal'skeletal support superfluous (cf. the different degree 
of development of the axostyle in the plastic Lop horn onas 
blattarum and the rigid L. striata). 
The relations of the axostyle to the nuclear apparatus seem 
to be difi:ereut in Lophomonas. There Janicki describes 
the central fibrils of the axostyle as traversing the calyx and 
nucleus and ending beneath the circle of basal granules : 
^^Irgeud welche direkten Beziehungen zwischen Basal- 
kornern und Kern konnten in Lophomonas nicht beo- 
bachtet werden.^^ Furthermore, the axostyle of Lopho- 
monas is re-formed by the division spindle, as in Tricho- 
monas batrachorum, Perty, and other allied flagellates. 
In Polymastix I could find no sign of this. 
Division. 
Early observers of Polymastix noted something unusual 
in the mode of division. Wahrscheinlich erfolgt die Ver- 
mehrung durch Querteilung (Doflein, 1911). Hamburger 
failed to find any evidence on this point. 
My own experience has been that, though the flagellate may 
be present in enormous numbers, it is very hard to find indi- 
viduals in division. Consequently I am able to supply only 
the outline of the process, but I have been so much struck by 
the general similarity between this and the division in Lopho- 
monas that I feel justified in publishing the figures. 
It should perhaps be noted first that the individuals with 
forked posterior ends, so commonly met with, are not dividing 
forms. I have watched the living organisms for long periods 
to satisfy myself of this, nor is there any indication of nuclear 
