( 906) 
isolate these micro-organisms that acetify rice among the mixture of 
moulds, fungi, and bacteria that fall out of the air on wet sterilized 
rice'). This micro-organism however was found after all. It is ¢ 
small, short rod, having great resemblance to the Colibacillus of 
the intestines. The isolation was rendered still more difficult because 
this little rod is very polymorph, and because a special medium and 
special breedingtemperature are required to obtain a good result.) 
This bacillus acetifies within 24 hours neutral sterilized rice, which 
but for this bacillus always remains neutral. 
Just now I have compared it to Colibacillus, on the other hand it 
reminds me of the vinegar bacilli by its polvmorphy. The more 
so, because it possesses the peculiarity, demonstrated by BrteRINcK 
in some vinegar bacteria, of showing on some special media easily 
deviating and hereditary qualities. So e.g. it is not difficult to deprive 
it of its power of exciting fermentation. According to BeIJERINCK 
there are’ also vinegar-bacteria that do no longer acetify, and must 
have originated in acetifying ones. Only on fit media, and when 
cultivated at the required temperature, and constantly having anew 
opportunity of acetifying rice, it is kept in good condition. It cannot 
he kept in rice, as it soon dies in the acid it has produced itself. 
Grow and multiply the bacillus does on the other hand on every 
medium that is not too sour, even though it afterwards dies or 
modifies itself in many of them. After domestication it accom- 
modates itself to altered cireumstances as to a feeding that was first 
refused or to a temperature at which in the beginning it was killed. 
Consequently we have here an exceedingly resisting bacillus, which 
could be cultivated in November and December in the whole 
laboratory. When however in December the temperature reached 
1) At the present moment this is not difficult, since | found out that moulds 
and fungi only multiply on rice, when the rice has obtained an acid reaction 
by the bacterium causing rice to turn sour. Consequently the moment when the 
rice that is at first neutral, begins to show a feeble acid reaction, must be 
carefully observed, then, in most cases, pure cultures of the bacillus acetifying 
rice will be obtained by inoculation on specially prepared ferment. This is still 
easier in winter when the air of the room that has grown perfectly dry by the 
heat of a stove so that scarcely any moulds and fungi are found in it. 
2) The first inoculation from sour rice very often had not the desired result on 
the common alkalic or acid media at 37°C., very often they do grow, but lose their 
power of fermentation. Rice which is in the first place indicated as a medium 
cannot be made into a transparent medium, On ferment and malt the best results 
are obtained at a temperature of 17—23° C. On ferment results are obtained to 
a temperature as high as 40°, on malt not. 1 owe the prescription for malt to 
Prof. Beterinck, the recipe for ferments was used and accidentally tried in this 
laboratory. Only on rice, glucose and malt acid is formed, 
