494 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
fungus; the more abundantly it is supplied with atmospheric air, the 
more luxuriantly it grows ; when immersed, the growth is feeble in pro- 
portion to the depth below the surface. The rarity of the air appears 
to favour its filamentous form of development. Of food-materials the 
carbohydrates are those which are most favourable to its growth, and in 
proportion to their high molecular equivalent. Slightly alkaline media 
are more congenial than neutral or acid. 
Lily- disease.* — Mr. A. L. Kean has investigated a disease which is 
exceedingly destructive in Bermuda to a variety of Lilium longijlorum , 
and finds it to be due to a species of Botrytis growing upon or within 
the leaves or flowers, in all probability identical with that described by 
Prof. Marshall Ward f as attacking Lilium candidum in this country. 
Production of Varieties in the Saccharomycetes.j: — More than a 
year ago Dr. C. C. Hansen succeeded in rearing varieties of Saccharo- 
mycetes which since this time have been cultivated without interruption 
in beer- wort, also in other liquid nutritive media and on solid media, 
or, in other words, they have been cultivated under very different con- 
ditions, and, nevertheless, have not regained their original faculty of 
spore-formation. In beer-wort especially, innumerable generations have 
been produced every fourteen days, and frequently new cultivations have 
been oftener effected. The transformation which the cell-protoplasm 
has undergone has therefore been of a nature so profound that it has 
been transmitted from generation to generation, and there does not seem 
any likelihood that it will disappear as long as the cells are cultivated 
in wort. Hence, in general terms, the principal result of the author’s 
experiments has been the production of varieties, the new characters of 
which are retained in the most diverse cultivations. 
About the methods whereby he has effected these changes the author 
gives only general indications. These are that cultivations were made 
from a low yeast at a temperature just below that which prevents budding. 
The cultivation-medium was beer-wort. Although the cells had lost 
their power of developing spores, they were still actively reproductive, 
and capable of exciting alcoholic fermentation. 
Action of Alcoholic Ferments on various kinds of Sugar. § — The 
examination, by Prof. E. C. Hansen, of the action of forty kinds of 
yeasts on saccharose, maltose, lactose, and dextrose, showed that, with 
the exception of the endosporous S. membranifaciens , all species of the 
genus Sciccharomyces possess the power of forming invertin and exciting 
alcoholic fermentation in saccharose and dextrose. On the other hand, 
S. marxianus, exiguus, and apiculatus, like the Torulae, were unable to 
ferment maltose, although this is decomposed by the rest of the Saccharo- 
mycetes, by Monilia Candida , and the Mucor yeasts. Monilia Candida is, 
moreover, the only yeast which decomposes saccharose directly without 
the previous formation of invertin. Mucor erectus excites fermenta- 
tion in saccharose solution, but not in that of dextrose. Only a single 
alcoholic yeast, that discovered by Duclaux in 1887, fermented lactose. 
* Bot. Gazette, xv. (1890) pp. 8-14 (1 pi.). f Cf. this Journal, 1889, p. 265. 
% Annales de Micrographie, ii. (1890) pp. 214-21. 
§ Op. c., i. (1888). See Bot. Centralbl., xxxix. (1889) p. 160. 
