502 Wager. — On N tic tear Division 
mination of such a point a matter of great difficulty. It is 
not safe to affirm, therefore, that it does not occur. 
The nucleolus has persisted all this time, and is still visible 
as a small body, which stains light blue (Figs. 9, 11, 39), but 
it now begins to disappear entirely, and in the majority of 
cases has completely vanished, by the time the chromatic 
elements have reached the poles of the spindle. Cases occur, 
however, in the division of the daughter-nuclei, as will be seen 
later on (Fig. 23), where the nucleoli persist until the chro- 
matic elements have reached the poles of the spindle and 
are in a state of fusion. In any case they disappear before 
the complete formation of the daughter-nuclei. 
When the chromatic elements arrive at the poles of the 
spindle, they begin to fuse together into two irregular masses 
which stain bright red (Figs 13-16.) Some, one or two, 
threads of the spindle-figure remain for some time connecting 
them together (Fig. 42), but eventually they disappear. The 
two masses thus formed are generally in close contact with 
the wall of the basidium ; in some cases they even produce 
a slight bulging out of the latter. 
The subsequent changes which take place in the formation 
of the daughter-nuclei are slightly different in the two species. 
In A. muscarius the new membranes for the daughter-nuclei 
now appear. The chromatin-mass in each remains in a parie- 
tal position, near the wall of the basidium. Radiating from 
this red mass in each nucleus, a few fine threads can be made 
out (Fig. 43), forming a faintly-stained network. The nuclei 
then increase in size. The chromatin-masses become appa- 
rently transformed into nucleoli, which gradually increase in 
size, whilst the network becomes more and more distinctly 
differentiated, until, at last, the two nuclei come to resemble 
the parent nucleus, both in structure and staining properties 
(Fig. 44). 
In A. stercorarius the chromatin-mass appears to be trans- 
formed at once into the nucleolus, and for a time there is 
a clear space between the nucleolus and the nuclear mem- 
brane. The outline of each nucleus is at this stage very 
