294 Prof. J. E. Salvin Moore and Mr. A. Breinl. [Mar. 9, 
Preparations of the blood during early stages of infection show the 
trypanosomes to be increasing in numbers through rapid longitudinal fission, 
accompanied by amitotic division of the nucleus and the extra-nuclear centro- 
somes (Plate 8, figs. 1—4). As the disease advances, two series of structural 
changes in the parasite become apparent; one of these (figs. 6—10) consists 
in a gradual increase of the nuclear substance towards the side away from the 
extra-nuclear centrosome, until, after forming a distinct protuberance, the 
mass separates from the nucleus and passes away towards the free end of the 
flagellum in the manner represented in figs. 8, 9, and 10. 
It is only possible at present to describe the existence of this process. It 
may be related to the formation, or rather the renewal, of the so-called 
“trophic granules,’* but we cannot decide this matter at the present time. 
The other process to which we have referred is of a totally different order. 
Towards the end of an infection, that is to say, on the third day after the 
appearance of the parasites in the blood, numbers of trypanosomes are 
observed, wherein the extra-nuclear centrosomes become conspicuously large 
(figs. 11, 12), and at the same time there exist others, in which it is seen 
that the extra-nuclear centrosome is budding off a large mass towards the 
nucleus. This mass becomes detached, and can be found in many individuals 
passing away towards the nucleus (figs. 12, 13, 14). There is often a distinct, 
but faint, suggestion of a protoplasmic thread still connecting the detached 
body with the extra-nuclear centrosome at the base of the flagellum (figs. 
12, 13, 14). Whiie this process is going on the intra-nuclear centrosome 
moves towards the extra-nuclear centrosomes, as in figs. 13, 14, and in a 
number of trypanosomes stages may be found in which the detached portion 
of the extra-nuclear centrosome is seen to pass completely through the body 
of the trypanosome until it becomes applied to the nucleus, as in figs. 15, 16. 
Some time later, the detached portion of the extra-nuclear centrosome merges 
with, and becomes indistinguishable from, the nuclear substance, and the 
trypanosomes again pass through division, as in figs. 16,17 (Plate 9). As 
division sometimes begins again before the detached centrosome is fused 
with the nucleus, the process can have nothing to do with any sort of 
degeneration. 
The process we have just described in the parasite of dourine is clearly 
analogous to the production of the stainable band in 7. gambiense. It 
differs only in there being a detached mass which passes from the extra- 
* It is curious to note that Laveran and Mesnil, Joc. cit., p. 273, are under the impres- 
sion that one of the specific characters of 7. eqguiperdum is constituted by the absence of 
protoplasmic granulations ; whereas, on the contrary, we have found them in abundance. 
It is impossible to say upon what this difference of condition depended. 
