460 
When the nucleus is at rest the intra-nuclear centrosome is 
surrounded by a light space, which is in turn enclosed by the stainable 
nuclear substance (fig. 47). During division the intra nuclear centro¬ 
some divides, as in figs. 48 to 52. The nuclear substance becoming 
at the same time collected up in the region of the dividing intra¬ 
nuclear beads. As this process continues, the nuclear substance 
eventually forms itself into two cup-shaped masses situated 
around, and beyond the intra-nuclear centrosomes. Owing 
to this, when Trypanosoma eguinum is dried the edges of 
these cups becoming flattened down produce at least two irregular 
bands on each side of the intra-nuclear centrosomes, which under 
these circumstances may suggest the existence of nuclear chromo¬ 
somes. This appearance is, however, misleading. The nuclear 
division of Trypanosoma eguinum being, as can be seen from figs. 
47 to 53, really amitotic, as in the case of Trypanosoma gambiense 
and Trypanosoma brucei. 
(E) CONSIDERATION OF THE FOREGOING OBSERVATIONS 
For the sake of convenience, it is desirable to consider the latent 
forms as the starting point in the life cycle of Trypanosoma 
gambiense. These bodies, which in an ordinary fluctuating infection 
may remain unchanged for long periods in the organs (and, to a less 
extent, in the blood), consist at first of a nucleus containing an intra- 
ce iular centrosome. The nucleus is related to a vesicle, and the 
w o e nuclear apparatus is surrounded by a delicate film of proto- 
p m. t a later stage, the intra-nuclear centrosome divides into 
two, and one of these bodies passes out of the nucleus into the outer 
layer of protoplasm, which gradually increases in extent. 
centro, 6 abOVe P rOCess results ” the formation of an extra-nuclear 
with th° me t hC eXtra " nudear centrosome, and nucleus together 
Itinct set f T centrosome, henceforth form two entirely 
senes If d StrUCtUreS ' which re ™,n distinct through a very long 
series ot divisions, as represented in j- , 
the letter B. P d in the dia g ram on page 445, under 
