the Yeast Plant. 
73 
hydrazine. No reduction was obtained. Specimens kept in the molybdate 
solution for half an hour gave a very slight green reaction in the nucleolus 
and surrounding granules. 
Behaviour of the Nucleus during Budding and Spore- 
formation. 
In the process of bud-formation the nucleolus becomes elongated and 
constricted and divides into two equal or unequal masses, one of which, 
together with a part of the nuclear vacuole and chromatin granules, passes 
into the young bud. The division of the nucleus may take place either 
entirely in the mother-cell, or the final separation may be accomplished in 
the neck joining the bud to the mother-cell. The granular chromatin 
mass round the nucleolus is also more or less equally divided along with 
the nucleolus. The division is a direct one, and there is no trace of 
anything in the nature of a mitotic figure with chromosomes and nuclear 
spindle. 
In the early stages of spore-formation, a large number of bright 
refractive granules appear in the cell. From their reactions towards stains 
Wager (’ 98 ) regarded them as of a proteid nature, but Guilliermond found 
that they possess the characteristic properties of the metachromatic granules 
discovered by Babes in the Bacteria and Cyanophyceae, which Biitschli 
called red granules and which have been more recently named volutin 
by A. Meyer. In order to get rid of these granules it is quite sufficient to 
fix the cells in Perenyi’s fluid. Cells thus fixed show clearly, when treated 
with appropriate nuclear stains, the granular chromatin network in contact 
with the nucleolus. The bright refractive volutin granules are easily seen 
(Wager, ’ 98 ) in the living cell ; the chromatin granules only after fixing 
and staining. Guilliermond has apparently confused these two sets of 
granules, taking it for granted that the bright refractive granules observed 
in the living cell are the same as the chromatin granules which are visible 
in the dead stained cells. As a matter of fact, the two sets of granules are 
entirely different in their appearance and staining reaction. 
The changes which take place in the nucleus immediately preceding 
its division into the spore nuclei are difficult to follow, and we have very 
little to add to what has already been given by Wager (’ 98 ) and other 
observers. The chromatin network first of all contracts round the nucleolus 
(Fig. 113), and the nuclear vacuole disappears (Figs. 114, 115). The 
nucleolus at this stage is frequently obscured by the chromatin granules 
and the remains of the chromatin network around it. The whole mass 
often presents the appearance of a deeply stained irregular body. The 
actual structure can, however, be brought out by staining in safranin and 
