602 Dr. E. F. Armstrong. [July 29, 
Grove Johnson,* is remarkable on account of its ability to withstand a 
temperature as high as 83° C., and as being most active at 45°; S. exiguus 
differs from S. Marxrianus in that the latter forms a membranous film; 
S. anomalus and S, Saturnus are characterised by the occurrence of both acids 
and fruit ethers among the products of their fermentative activity. The 
other yeasts are characterised by the manner in which they undergo repro- 
duction, as their group names show: the torule do not form spores; the 
schizosaccharomyces multiply by fission; S. capsularis forms spores with two 
enveloping membranes; and S. apiculatus, which is very common on fruits 
in the late summer and autumn, occurs in very characteristic, small, lemon- 
shaped cells. 
The method adopted was as follows: The yeasts, which in nearly all cases 
had been obtained from the Carlsberg Laboratory, were cultivated in beer 
wort; subcultures consisting of quite young cells not more than 24 hours old 
were always used in the actual experiments. The sugars were highly 
purifiedt and were used in the form of 10-per-cent. solutions in yeast water. 
A single drop of the yeast sediment was introduced into about 10.c.c. of the 
sterilised sugar solution contained in a Freudenreich flask, with the rigid 
precautions prescribed by Hansen to ensure sterility. The solutions weie 
maintained at 25° while under observation. Up to the present time, the 
experiments have been made solely with the object of ascertaining whether 
or no the organisms were able to bring about the fermentation of the various 
sugars. | 
In positive cases, the evidence of the occurrence of fermentation afforded 
by the rapid evolution of small bubbles of gas, especially on shaking, was 
unmistakable. Sometimes only a very few bubbles were observed to escape: 
such a result was regarded either as indicating the presence of traces of 
impurity or as due to the fermentation of glycogen in the yeast. In most 
cases the production of alcohol was confirmed by distillation. As a rule, the 
occurrence of fermentation was evident within 24 hours and was very 
marked within 48 hours. 
The present communication is intended to be only a preliminary note; it 
is proposed to discuss the full bearing of the results in a subsequent commu- 
nication in connection with those of other workers and the theories of 
fermentation. 
* ‘Journ. Inst. Brewing,’ 1905, vol. 11, p. 466. 
+ It may be well to point out here that many samples of galactose contain traces of 
glucose ; in fact, to remove all traces of glucose from commercial galactose, it is necessary 
to subject it to the action of a yeast such as S. Ludwigit, which ferments glucose readily 
but is without action on galactose. 
