506 Wager . — On Niiclear Division 
also suggested that those parts of the nucleus which stain blue 
contain nuclein, whilst those which possess no nuclein stain red. 
This seems to me to hold good for resting nuclei generally, 
but as a test for nuclein in dividing nuclei it fails. It is inter- 
esting in connexion with this to note that the nucleolus in the 
basidium of the Hymenomycetes, when the larger part of its 
substance has become dissolved, stains blue ; and Zacharias 
points out, in the paper above quoted, that if epidermal cells 
of Galanthus nivalis be placed in digestive fluid, the network 
of the nucleus and the remains of the nucleolus stain blue 
after a time. It appears to me, therefore, that both network 
and nucleolus contain substances which give the cyanophil 
reaction at certain times. In the resting nucleus the blue 
staining of the nucleolus is masked by a substance which has 
the erythrophil reaction, whilst in the stages of division the 
blue of the threads becomes masked by a substance which 
also possesses the erythrophil reaction : and as the threads 
become erythrophil, the erythrophil character of the nucleolus 
disappears. 
Division of the Daughter-Nuclei. 
The division of the two daughter-nuclei takes place in the 
same manner as the primary division already described. The 
nuclear membrane, however, persists for a very much longer 
time. 
A. stercorarius. When the daughter-nuclei are completely 
formed, they 'lie in a transverse plane near the apex of the 
basidium, and, as already mentioned, take up nearly the whole 
of its diameter. When about to divide, they first of all 
elongate transversely along a line passing through the centre 
of each nucleus. The two nuclei come into close contact, 
and, as there is no room in the basidium for any very 
considerable elongation in the transverse direction, further 
elongation takes place in an obliquely upward direction. The 
two nuclei thus form an obtuse angle with one another, the 
apex of which points to the lower end of the basidium. The 
free ends of the nuclei come into contact with the wall of the 
