SUMMARY OF CURRENT RESEARCHES RELATING TO 
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as a direct division of the nucleole into two equal or nearly equal parts, 
accompanied by division of the chromatin vacuole, network, or granules. 
The nucleole divides either in the neck joining the bud to the mother- 
cell, or more rarely in the mother-cell itself, one of the products of 
division passing subsequently into the bud. In spore-formation the 
chromatin disseminated through the protoplasm becomes more or less 
completely absorbed into the nucleole, which then divides by elongation 
and constriction into two. During the division, deeply stained gra- 
nules appear, surrounded by a less deeply stained substance, which 
remains for a time connecting the two daughter-nucleoles. This may 
possibly indicate a simple stage of karyokinesis. Subsequent divisions 
take place, resulting in the formation of four (sometimes more) nucleoles. 
Each nucleole becomes surrounded by protoplasm and a delicate 
membrane ; and thus are formed the spores standing free in the remain- 
der of the protoplasm. The spores are at first very small, but they 
soon increase in size ; the surrounding protoplasm becomes used up ; the 
spore-membranes increase in thickness, until at last, in the mature con- 
dition, they completely fill the mother-cell. 
Prof. L. Errera * also finds a relatively large nuclear body in every 
adult cell of Saccharomyces Cerevisise. 
Alcohol-producing Enzyme of Yeast.t — From a fresh series of ex- 
periments on both high and low fermentation yeasts, Prof. J. R. Green 
is led to modify to some extent his previous conclusions, and to agree 
with those of Buchner J as to the production of an alcohol-producing 
enzyme. When the yeast-cells are active, they secrete an enzyme 
which can be extracted by appropriate means, and then sets up fermenta- 
tion in sugar solutions under conditions which prevent the activity of 
living yeast. The enzyme is easily decomposed, and its secretion by 
the cell is intermittent, taking place only during actual fermentation by 
the yeast. 
Sorghum Blight and Yeast Parasitism. §— By infecting sorghum 
with different kinds of yeasts, M. Radais has demonstrated that yeasts can 
develop in the living cells of sorghum, and that the parasitism of these 
yeasts is capable of exciting a deep red staining of the tissues of the 
plant. This staining is quite the same as is observed in the disease 
called sorghum blight. The pigment is therefore the production of the 
diseased cell, and the parasite is only indirectly concerned therein. These 
results confirm the hypothesis of Palmeri and Comes, and are not op- 
posed to the views expressed by Burrill, Kellermann, and Swingle. They 
amount in fact to the statement that the red coloration is the result of 
the chromogenic function of the diseased cells, and that this staining 
may be caused by diverse parasites, yeasts or bacteria. On the other 
hand they are opposed to the conclusions of Bruyning, who attributed 
the phenomenon to chromogenic bacteria. 
Organisms isolatsd from Cancer, and their Pathogenic Effects on 
Animals. || — Mr. H. G. Plimmer isolated from a cancer an organism 
* Tom. cit., pp. 367-8. 
t Ann. of Bot., xii. (1898) pp. 491-7. Cf. this Journal, 1898, p. 219. 
+ Of. this Journal, 1897, p. 414. § Comptes Rendus, cxxviii. (1899) pp. 445-8 
|| Proc. Roy. Soc., lxiv. (1899) pp. 431-6. 
1899 
Y 
