510 SUMMARY OF CURRENT RESEARCHES RELATING TO 
Granules and Vacuoles of Yeast-cells.* — Herr J. Raum examined 
ten different kinds of yeasts for cell-nuclei. The yeasts used were in 
pure cultivations, and they were stained and fixed in different ways. 
He came to the conclusion that true nuclei were not present, although 
he found in all the species examined those peculiar bodies known as 
sporogenic granules. These, when stained with methylen and Bismarck- 
brown, become black or dark brown, and when treated with eosin or 
rose-Bengale and methylen-blue became dark violet. These granules 
are by no means invariably present, being found only when the con- 
ditions of nutrition are favourable, and are absent in badly nourished 
and senile forms. With regard to number, shape, and arrangement 
within the cell, the granules exhibit great variation, though these remain 
very much the same for each species. No membrane or any definite 
structure could be observed ; hence they are probably of fluid consistence. 
Though their chemical composition is not yet ascertained, their digesti- 
bility by means of pepsin suggests that they are of the nature of nuclein. 
The author also found that vacuoles are of frequent occurrence in 
yeast-cells, but are not always present ; e. g. they are absent altogether 
in kephir yeast, and their size is in inverse ratio to that of the granules. 
From observations on cells while budding the author finds that neither the 
vacuoles nor granules are connected with this process. Nor is there any 
direct connection between the granules, the vacuoles, and spore-formation. 
Animals, when infected with pure cultivations of yeast, suffered from 
fever and dyspnoea ; and it was noticed that yeast-cells from internal 
organs behaved differently towards stains to what they did when culti- 
vated in fluid nutrient media. 
Saccharomyces.f — Prof. E. C. Hansen defends the independence of 
the genus Saccharomyces against the attacks of H. Moeller, who advo- 
cates the extension of the term. The latter declines to believe that 
certain forms seen within yeast cells are true spores, inasmuch as they 
do not possess a spore-membrane, nor have they been observed to 
mature into germs ; and, as there is for him no morphological difference 
between Ustilago sporids and the yeasts examined by him, the genus 
Saccharomyces should be enlarged. 
According to the author, not only are these forms enclosed in a 
membrane, but every step in their after development can be observed 
under the Microscope. Hence, they are really endospores ; and he goes 
on to say that among the Blastomycetes or yeast-fungi there exists a 
group embracing numerous species, which differ from the rest of the 
Blastomycetes in the internal development of spores. This particular 
group has been introduced into the system under the generic appellation 
of Saccharomyces. He holds that it is better to adhere to the old name 
until the conjectural original form is discovered. Then will be time 
enough to extend the definition of genus Saccharomyces. 
Fermentation Differences of Wine Yeasts.| — The experiments of 
Herr J. Wortmann on wine yeasts from various wine districts were 
* Zeitschr. f. Hygiene, x. (1891) pp. 1-50. 
t Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 16-9. Cf. this Journal, 
ante , p. 220. 
X Landwirthschaftliche Jakrbiicher, xxi. (1892) pp. 901-36. See Bot. Centralbl., 
liii. (1893) pp. 318-9. 
