234 
H. M. WOODCOCK. 
this worker considers that he oi>taiued evidence whicli pointed 
to a Trypanosome enveloping a red blood-cell and proceeding 
to “take np ” its nucleus. As we emphasized in our papei-, 
we searched in vain, time after time, for signs of such a 
metamorphosis ; the utmost we found to occur was the 
attachment merely of a Trypanosome to an erythrobhist or 
a uninuclear leucocyte by one extremity, which might be 
either the flagellar or the aflagellar one. Two features very 
difficult to explain on the assumption that a Trypanosome 
thus passes into or becomes a Le ucocytozoon are (a) the 
fact that the latter parasite, in its well-known form, shows 
always male and female individuals, whereas a similar dis- 
tinction cannot be made out in the case of the Trypanosomes ; 
and (b) the fact that quite small intra-cellular Leucocytozoan 
parasites occur, which certainly grow up into the characteristic 
adults, since intermediate-sized forms can be found. With 
regard to the remarkable phenomenon described by Prowazek 
of a parasite (a so-called “agamont”) becoming separated 
from its original host-cell, but taking a part of the nucleus 
and the cytoplasm of the latter with it and penetrating with 
these elements into a fresh host-cell, I can only say 
that in all my experience I have never seen anything which 
could in the remotest degree suggest such an occurrence. 
Prowazek’s figs. 2-5, pi. i, are supposed to show different 
stages in this process; but I cannot gather anything of the 
sort from them. Lastly, Prowazek also considers that the 
gametocytes of L eucocy tozoon undergo a division, usually 
into two, which is considered to be longitudinal and thus to 
indicate the Trypanosome-character of these forms. The 
author says that both male and female forms may so divide, 
but adds the very significant remark that in some cases the 
two residting individuals are not of the same sex, but one is 
male and the other female. From Prowazek’s figures 8-17, 
it is perfectly clear that we have really to do here with the 
same condition which I have described in Halteridium 
(10), and which had been previously found in Haemocys- 
tidium. As I discussed in that note, there can be little or 
