333 
Centrospheres in Fungi. 
Fig. 4. Basidium with two larger nuclei ; chromatin coloured bright red 
nucleoli distinctly visible and coloured dark reddish purple. Each of these two 
nuclei has probably been formed by fusion of nuclei similar to those in Fig. 3. 
Fig. 5. Basidium with two nuclei separated from each other by a vacuole. 
Nuclei somewhat larger than in Fig. 4. The archoplasmic bodies, c, are now- 
visible for the first time and are coloured faint blue. They are in close contact 
with the nuclei, and look almost as if they were being extruded from them. 
These nuclei have probably arisen by fusion of such nuclei as in Fig. 4 ; the 
chromatin-network is contracted away from wall of nucleus just as it is in cases 
of fusion of older nuclei. 
Fig. 6. Young basidium with two nuclei, later stage. Chromatin-network 
very dense, coloured red. Nucleolus dark red. Near each nucleus, but distinctly 
separated from it, is the archoplasmic body, which stains light blue. 
Fig. 7. Basidium with two nuclei just beginning to fuse together ; the granular 
network clearly visible. Two archoplasmic bodies on opposite sides of the 
fusing nuclei. Nucleoli bluish red, network also bluish red, archoplasmic bodies 
faint blue. 
Fig. 7 a. Basidium with nuclei just after fusion. The two nucleoli still dis- 
tinctly separated from one another. Archoplasmic bodies at opposite sides of the 
nucleus. 
Fig. 8. Much later stage. Nucleus much elongated. Nucleus threads now 
distinct with chromatin-granules. Nucleolus large ; archoplasmic bodies close 
together at apex of nucleus. The nuclear network appears to be breaking up 
into separate equal sized threads. 
Fig. 9. Slightly later stage. Nucleolus at extreme apex of nucleus. Archo- 
plasmic bodies have fused together and now appear as a slightly elongate light 
blue body. 
Fig. 10. Archoplasmic body at some distance from apex of nucleus which is 
still in same position, about halfway between apex and base of the basidium, 
as in Figs. 8 and 9. Nucleolus still at extreme apex of nucleus. 
Fig. 11. Basidium with nucleus nearer its apex. Archoplasmic body in close 
contact with the nucleus in upper part. Nucleolus now halfway down. 
Fig. 12. Archoplasmic body at apex of nucleus. Nucleolus now at opposite 
end. 
Fig. 13, Later stage. Chromosomes, condensing at apex of nucleus, deep bright 
red in colour. Near these lies the archoplasmic body, somewhat irregular in 
shape. At the base two bodies in close contact with each other, light blue in 
colour. These are due to division of nucleolus, which sometimes takes place 
at this stage. The nucleolus loses its colour also at this stage. 
Fig. 14. Nearly same stage as Fig. 13, or perhaps little later. Archoplasmic 
body is not now visible. 
Fig. 15. Transverse section of basidium, showing a few chromosomes and the 
centrosomes from which radiating striae are beginning to pass. The centrosomes 
are stained light blue. This is a stage just before spindle-figure becomes clearly 
visible. 
Fig. 16. Longitudinal section of basidium, cut somewhat obliquely to the 
plane in which centrosomes are placed, so that only one of these is visible. 
