EEPROBUCTION OF KALPIDORHYNCHUS ARENICOL/E. 567 
others in the formation of the first spindle in the Gregarines, 
but most closely with the facts in Monocystis ascidice 
(R. Lank.)j Siedlecki (1900), and those in G. ovata as 
described by Schnitzler (1905), for here there is no vesicle. 
The divisions proceed very rapidly; still, I was fortunate 
enough to find a cyst with only two nuclei, both, however, 
dividing (fig. 3). 
In a stage with a small number of nuclei it could be seen 
that in the late anaphase the spindles stretch out, and become, 
consequently, very much attenuated in the middle. Thus the 
two daughter-nuclei arising from a division seem, at any 
rate during the rearrangement of the chromatin, to be 
surrounded and supported by the wide ends of the spindle 
of the mother-nucleus (figs. 4 a and h). Siedlecki (1900) and 
Brasil record the same method of division in Monocystids, 
and Brasil says that it seems as though the fibres of the 
spindle helped largely in forming the membranes of the 
daughter-nuclei. I did not notice that division went on 
more rapidly at the periphery of the cyst than elsewhere. 
In these early stages the centrosomes could be easily 
demonstrated, and sometimes a sphere could be seen lying 
completely within the nuclear membrane showing its intra- 
nuclear origin (fig. 5). It would seem, too, that the spindle 
in these divisions is formed within the nuclear membrane, 
which only disappears when the spindle is fully formed 
(figs. 5 a and 5 h). Most of the nuclei contain two or three, 
some four, spherules of chromatin. These are probably 
karyosomes, though on account of their small size it is 
impossible to demonstrate two layers in even the largest of 
them. 
In a few of the cysts, all of about the same age, i.e. 
having approximately the same number of nuclei, a small 
sphere of chromatin could be seen being thrust out of each 
nuclear spindle during division. It is worthy of note that if 
one spindle in a cyst showed this every other spindle in that 
cyst did so too. This cannot be regarded as a case of 
Reduction, for the number of the chromosomes remained 
