204 
II. M. WOODCOCK. 
more prominent chromatic grains. In this comiection it 
must be noted tliat i\Iiss Robertson (28) mentions and 
fre(piently figures a small but definite granule in the nucleus 
of II. nico rim, which is in no way distinguishable from the 
pcrij)heral chromatin grains in size or staining reaction, but 
which nevertheless appears to be different from the other 
nuclear elements in so far that, in tlie primitive type of nuclear 
division, it seems to form a centrodesmose. This minute 
body may well be the centrosome; just as the central granule 
which I have sometimes noted in the nucleus of K. lacertm, 
when there is no longer a distinct karyosome, is also probably 
one (cf. fig. 40). 
It is a pity that Reichenow, in his able memoir, should 
have thought himself at liberty to disn'gard or treat as 
negligible the evidence afforded by the research of other 
earlier workers, such as the classic instances of Coccidium 
schubergi and Cy clospora caryoly tica, made known by 
Schaudinn (30 an d 31), which pointed clearly to the existence 
of this characteristic promitolic division of the karyosome in 
the respective parasites, and which has since been abundantly 
corroboi'ated in other cases ; to saj' nothing of his having 
entirely failed to take into consideration that in several of the 
lower Flagellates the occurrence of a centrosome and of 
])romitotic division of the karyosome is now well established. 
As it is generally agreed to-day that the Ectospor.-i (Telo- 
sporidia) are descended from Flagellate ancestors, it might 
be expected, on a priori grounds alone, that among Coccidia 
and llmmosporidia some would be found to exhibit a similar 
mechanism in their nuclear division. 
I certainly do not think it is advisable to adopt such a 
comprehensive generalisation as that postulated bj^ Hartmann 
and Chagas and the followers of their school, namely, that a 
central organella (centrosome) is present, as a general rule, 
in the karyosome of all Protozoa; but I will at once admit 
that I consider this idea considerably nearer the truth than 
the view maintained by Richenow, that a centrosome is not 
present in the karyosome in any of the cases mentioned 
