232 Barker.—A Fragrant ‘Mycoderma ’ Yeast , 
in small quantities, among which amyl and butyl alcohols are 
predominant. 
Organic acids. The fermented liquids show a well-defined 
acid reaction to litmus. Acetic, butyric, and succinic acids 
have been found. 
Fruit ethers. One of the most conspicuous points in con¬ 
nexion with the fermentation brought about by this Yeast 
is the strong odour of fruit ethers that is developed after 
active fermentation has been in progress for some time. The 
exact odour varies, but that of ethyl acetate in some cases, and 
that of amyl acetate in other cases, are predominant. The 
odour in beer-wort fermentations is not as strong nor as well 
defined as in the cases of dextrose, saccharose, and laevulose. 
History and Bibliography. 
In 1891 Hansen ( 1 ) published a paper, Sur la germination 
des spores chez les Sac charomycetes , in which he gave a short 
description of a new species, belonging to that genus, which 
he named S. anomalus. The organism was characterized 
by an extremely quick film-formation on beer-wort, the film 
appearing at the beginning of fermentation, by the pro¬ 
duction of a strong odour of ‘ fruit-ethers ’ during the course 
of fermentation, and by the resemblance of the organism, 
when viewed under the microscope, to certain Tortda-forms. 
During fermentation a strong odour of ‘ fruit-ethers ’ is pro¬ 
duced. It was capable of forming spores under similar 
conditions to those required by other species of Saccharomyces , 
and they were also to be found plentifully in old cultures. 
They differed from the spores of all other species of Sac¬ 
charomyces in their shape: they were hemispherical, with one 
surface flattened, and they had a projecting rim round the 
edge of the flattened surface. Hansen called them 4 hat- 
shaped,’ and pointed out that they were identical in form 
with those of Endomyces decipiens ( 18 ). On germination they 
gave rise to no pro-mycelium, but, instead, produced buds 
similar to those developed by ordinary vegetative cells. The 
paper concludes with a short reference to the possibility of 
