BY R. GREIG SMITH. 653 



same time two small bottles of unpasteurised wine were placed 

 under observation. All the bottles were incubated at 22° C. for 

 three weeks, when it was found that the pure yeasts, although 

 still alive, had not grown, and it was evident that they were not 

 responsible for the trouble. The unpasteurised wine was turbid, 

 and had a thin surface film and a slight precipitate. During the 

 experiment it was noted that a growth occurred first upon the 

 surface of the unpasteurised wine and then spread downwards. 

 An examination of the film revealed a zoogloea mass of bacteria. 

 The same kind of bacteria were obtained in the body of the 

 wine. On re-examining the original bottle of wine from which 

 the yeast had been obtained, it was seen that a film had by this 

 time formed, and it consisted entirely of bacteria similar to those 

 found in the experimental bottles. The film had probably been 

 present at an earlier stage, but it had been so slight as to be 

 obscured by the dark colour of the glass of the bottle. 



The investigation had so far advanced as to indicate the 

 infecting organism, and in order to obtain it in pure culture, 

 plates of nutrient agar and peptone-glucose-gelatine were prepared, 

 but no growth appeared in these. The fact that the organism 

 does not grow upon these media explains how I did not obtain it 

 in my earlier experiments. Neither did it grow on nutrient 

 glucose-gelatine. Colonies were, however, obtained upon plates 

 of nutrient agar to which about one-third of the volume of 

 pasteurised wine had been added while the agar was fluid. The 

 culonies appeared at the end of four days when grown at 22° C. 

 as small white points. When magnified sixty-fold they appeared 

 round, brownish-black, and finely granular; the edges were smooth 

 and the colonies had each a dark central point (the starting point 

 of the colony). Within a central zone of half the radius of 

 the colony the granulation was darker than at the margin. The 

 deep and subsurface colonies appeared irregular, rough and 

 slightly moruloid. The colonies enlarged, becoming round, white 

 and glistening like a drop of wax. The middle of the colony 

 was raised. The bacterial colonies derived from the original 

 bottle of wine and from the wine from the storage cask, were 



