N. H. SWELLENGREBEL 
467 
division (“ leptomonas-forms ”) may divide again before recovei’ing the 
normal shape of a trypanosome (fig. 2). These forms have been called 
“latent bodies” by Moore, Breinl and Hindle, who seem to think that 
they are resistant bodies. Why they are called “latent” I cannot 
imagine, for they divide and move about, and are as active as ever they 
can be h 
There may also occur (though not very often) an equal multiple 
division without the production of a rosette (fig. 4). Many nuclei and 
flagella are formed and the probable result is the production of flagellates 
of the normal shape and size, although I cannot say this with certainty 
because I only met stages as drawn in fig. 4. So far as I know this 
mode of division of T. lewisi has not yet been described. This multiple 
equal division leads to the binary equal <livision (fig. 3) already 
described by Swingle (1907). I never saw any stage but that shown of 
fig. 3, so I do not know whether division actually takes place at this 
stage or not. Perhaps fig. 3 represents only a stage previous to 
the one shown in fig. 4, so that both of them belong to the same mode 
of division. Fig. 6 shows unequal binary division, very seldom to be 
observed ; I saw it only once. 
(6) Nuclear division. (Diagram VIII.) Two types may be dis¬ 
tinguished : (a) a division in which a karyosome seems to take a leading 
part; (b) a division where no central chromatic mass is to be seen. 
Type (a) (figs. 1—6). The nucleus becomes elongated and the karyo¬ 
some takes the shape of a dumb-bell (fig. 1); often, though not always, 
the two poles of the dumb-bell are united to the periphery of the 
dividing nucleus by radiate fibrillae. The karyosome divides (fig. 2), the 
nucleus becoming more and more elongated. The two karyosomes may 
divide again before the nuclear division is complete (fig. 3). A clear 
space now appears in the equatorial region of the nucleus (figs. 4, 5) 
which becomes more distinct and indicates the line of demarcation of 
the two nuclei; they become rounded at the edges and the two 
daughter-nuclei are constituted (fig. 6). Sometimes the division of the 
karyosome is delayed, so that the nucleus is practically divided at a 
time that the two daughter-karyosomes are yet united by a filament 
(fig. 4). I did not often observe these stages, but sometimes they may 
be frequent and then the two nuclei may be separated by a long 
distance, the karyosomes still holding together by a very elongated 
filament as is shown in the figures of Moore, Breinl and Hindle and as 
I myself observed in Prof. Minchiu’s preparations. It is worth men- 
1 Fig. 4 (Diagram X) shows a curious spur-like appendix to such a “leptomonas form.” 
Its significance is unknown to me. 
