466 
animals had been preserved and dried, or to other forms of indifferent 
fixation. In other words, there are often produced during fission of 
the animals under such circumstances appearances in their nuclei due 
to coagulation effects which may readily he mistaken for nuclear 
chromosomes. As the fixation becomes better, in all the forms with 
which we have hitherto dealt, such appearances can, however, be 
clearly shown to be illusive, and the division of the nucleus during 
fission to be invariably amitotic in character The same inference is 
borne out by a study of the living animals. 
Among the illustrations given by Minchin [Proceedings of the 
Royal Society, Vol. 78, Series B, No. 20, Plate 12], figs. 4, 8, 9. and 1; 
have been produced from specimens that have been dried and stained, 
and suggest the existence of chromosomes, hut we are inclined to 
think that these appearances are simply due to the bad fixation 
methods employed, and are really quite misleading. 
With regard to the nature of the nuclear division accompanying 
fission of the above-mentioned trypanosomes, our results are m 
complete accord with those of Laveran. Indeed, with regard to the 
nuclear reduction described by Schaudinn,* and finally by Prowazek. 
our observations have revealed nothing suggesting anything even 
analogous to these descriptions. Prowazek gives a scries of figures 
illustrating this process in Trypanosoma lewisi (PI. II, figs. 23, 24, 
25). Here nuclei with eight chromosomes are said to be apparent 
\\ e cannot detect in the figures themselves the slightest suggestion 
of this being the case, and are inclined to think that the irregular 
blotches and strands, undoubtedly correctly drawn, have nothing to 
do with chromosomes, but are due to the manner in which the 
specimens have been preserved. In figs. 27, 28, 29, 30 and 31, the 
so-called reduction of the nucleus as well as the extra-nuclear 
centrosome (blepharoplast) is represented; but in none of these 
figures do we see any indication of either true chromosomes, true 
mitotic division, or true reduction as ordinarily understood. In fact, as 
ar as the illustrations are concerned, we are unable to find, or to see, 
any indication of a reduction process. 
It will thus be observed that the results we have obtained. 
— * n re ^ a ^ on to Trypanosoma gambiense , but also equally 
♦Generations und Wirtswechsel, &c. " 
t Loc. cit. 
