reducing. Hence it is sure that at the “emulsion reaction”, together 
with the non-reducing slime, an easily diffusing and reducing substance 
(probably a sugar) is formed. The chemical composition of this 
substance is still unknown, just like that of the slime itself. 
The possibility exists that the reducing substance is invert-sugar 
produced by invertase, which latter enzyme then should always 
accompany the viscosaccharase. Decisive experiments on this subject 
in progress. 
Viscosaccharase is a synthetically acting enzyme. 
As to the nature of the slime it must be accepted that its molecules 
are much larger than those of cane-sugar, else it would not be clear 
why the slime cannot diffuse through the agar, which cane-sugar does 
very easily. Viscosaccharase must therefore be a synthetically acting 
enzyme. This circumstance suggests a relation between the slime and 
“dextran” x ). This is, however, a substance forming the cell-wall of 
the concerned microbes, which substance may spread in water, and even 
to some extent diffuse into agarplates, but is not the product of an 
exo-enzyme, i. e. of an enzyme able to leave the bacterial body and act 
outside of it like the viscosaccharase. In relation to this it is not 
astonishing that “dextran” can very well originate from glucose and 
some other sugars, which do not produce the emulsion. 
Very remarkable is the fact that all the hitherto examined bacteria 
which show the emulsion-phenomenon, are able, at definite culture- 
conditions, for example on cane-sugar gelatin, when no emulsion is 
produced, to form non-diffusing “dextran”, by which their colonies then 
become visible on the plates as large transparent drops. This also 
points to a narrow relation between the two phenomena and leads 
to the conclusion that the drops of the emulsion must be identic 
with, or related to dextran. 
Perhaps by further research modifications of viscosaccharase will 
prove to exist, which also act on glucose and other sugars and from 
these may form “dextran”, but which cannot leave the body, or rather 
the cell-wall of the microbes, and must be considered as endo-enzymes 
whose product, which itself does not diffuse, cannot be found beyond 
the limits of the colony. 
If in accordance with my expectation, the emulsion is really brought 
about by “dextran”, then light will be thrown on the formation of 
the wall-substances of plant cells in general; for there is no doubt 
’) G. Scheibler, Zeitschr. d. Vereins fiir Rubenzuekerinduslrie, Bd.24, p.309, 
1374. h. Maquenne. beg sucres et leurs prineipau* arrives, p. 745, 1900, 
