209 
ceDtrosome. These little granules lie in the position from which new 
flagella finally arise, and it is consequently suggested that in T. lewisi 
the flagellum originates from a small fragment of the extra-nuclear 
centrosome, which becomes detached after the extra-nuclear 
centrosome has divided. This view of the method of procedure is 
further enforced by the fact that after the dissociation of the 
flagellum from the extra-nuclear centrosomes (which take place during 
the division of the latter bodies, see figs. 41-46), the original flagellum 
and its bead appears to be left, and is certainly finally shed in a 
degenerative condition, in the same way as the flagellum is cast off 
during the formation of the latent bodies in T. gambiense and 
T. equiperdum. From the vicinity of each of the new extra-nuclear 
centrosomes, and apparently from the granules budded off from these 
bodies, new and delicate flagella arise, and the multi-nucleated mass 
may assume in consequence appearances such as those represented 
in figs, 41.46. 
It will be seen that the features of the phase we have now 
described, that is, the production of the large pointed forms, the 
passage of an extra-nuclear-centrosomic derivative to the nuclei, the 
subsequent division of the nuclei, the formation of new extra-nuclear 
centrosomes, the degeneration and disappearance of the old 
flagellum and the formation of new flagella in association with new 
extra-nuclear centrosomes, certainly correspond in a biological sense 
'^’ith the phases we have considered and described in relation to the 
production of the latent bodies in T. gambiense and T. equiferdum. 
h would seem, indeed, that the multiplication of the nuclei in the large 
®ulti-nucleated masses of T. lewisi correspond to the division in 
equiperdum after the passage of the extra-nuclear-centrosomic 
derivative to the nucleus. The subsequent history of the multi- 
f'ucleated forms is equally interesting in this comparative aspect. The 
•Nuclei and the extra-nuclear centrosomes may become multi-nucleated 
bll there are 10, 15, or more of each in a single mass. The flagella 
become distributed on the periphery of such masses, and the mass 
My separates by forming either a mulberry-like aggregate of round 
flagellated forms, or the fission proceeds in a slightly different manner, 
^^d a curious group of somewhat elongated forms may be produced, 
k- 29. In all these resulting forms, whether elongated or round, 
morphological conditions are quite different from those of the 
