500 Wager . — On Nuclear Division 
they behave somewhat differently towards stain than before. 
They tend to take up the red stain, and in consequence 
become coloured reddish blue instead of deep blue, and are 
also more intensely stained. Between these granules a few 
delicate connecting threads, stained light blue, were to be 
seen. The segments, during their transformation into these 
granules, become considerably reduced in number, but I was 
not able to determine if this be due to their fusion. The 
nuclear membrane at this stage becomes irregular in outline, 
is less clearly defined from the cytoplasm, and soon afterwards 
almost completely disappears. 
The chromatic elements now group themselves in the middle 
line, near the apex of the basidium, to form a more or less re- 
gular equatorial plate (Fig. 38). They become smaller, brightly 
refractive, and stain, more intensely than before, a bright red. 
This renders them very distinct, and differentiates them most 
clearly from the surrounding cytoplasm, which is itself stained 
more deeply than before. The nucleolus, meanwhile, becomes 
very much smaller in size, loses its capacity for taking up the 
red stain, and instead of the reddish blue which formerly 
distinguished it, is now coloured only light blue, and is not, as in 
the earlier stages, the most conspicuous object in the basidium. 
Finally the nuclear membrane completely disappears, and 
the nuclear elements come to lie quite freely in the proto- 
plasm. The disappearance of the nucleoli is probably due to 
their solution in the nuclear sap, as is the case, according to 
Strasburger 1 , in the higher plants. At the time when the 
nuclear membrane disappears, the cytoplasm becomes more 
deeply stained. This is probably due to the escape of a 
portion of the dissolved nucleolar substance into it. From 
the fact that the chromosomes begin to stain red at the time 
of the disappearance of the nucleoli, it would further appear 
that the former can take up nucleolar substance from the 
nuclear sap, and as fast as the nucleoli disappear the chromatic 
elements become more deeply stained red. It is impossible 
1 Controversen der indirecten Kerntheilung, p. 8, 1884, and later works. 
