BY R. GREIG SMITH. 233 



These results show that the action of this bacterium upon 

 saccharose is precisely similar to that of Bac. levaniformans. The 

 relative amounts of levan and reducing sugars are about the same, 

 and there is also a similar hydrolysis of the levan by the secreted 

 acids in the old culture. On the 19th day the culture medium 

 contained an acidity equal to 0-135% of lactic acid. 



For the same reason that levaniformans was shown to secrete 

 invertase, so is it with this bacterium : the amount of acids 

 secreted in both cases is similar, and too small to account for 

 the heavy inversion, which must, therefore, be ascribed to the 

 action of an enzyme. 



During the bacterial fermentation, carbon dioxide is evolved. 

 This was made manifest by connecting the cultivation flask with 

 a bottle containing baryta water and aspirating air which had 

 passed over soda-lime, through the apparatus. A copious forma- 

 tion of barium carbonate occurred. 



The acids secreted by the bacterium were tested in the manner 

 already described for Bac. levaniformans* The chief acid formed 

 is lactic; capric, formic and acetic acids were detected. The 

 presence of butyric acid could not be definitely proved, which 

 may be accounted for by the fact that a young (6 days') culture 

 was used for the separation, and it is admitted in some cases of 

 butyric fermentation that the butyric acid is formed from the 

 calcium salt of lactic acid, which means that it is formed at a 

 later stage of the fermentation. 



It would appear that in the presence of calcium carbonate the 

 reducing sugars are used for the formation of acid. A chalk 

 culture which had been incubated for 12 days at 30" contained 

 the following ccmstituents per litre : — 



Saccharose ... ... ... ... .. 12 £frms. 



o 



Mixed reducing sugars ... ... ... 18 ,, 



Levan ., ... ... ... ... 32 ,, 



The saccharose and levan are in the proportions and amount 

 which were found under ordinary conditions of cultivation both 



* These Proceedings, 1901, Pt. iv., p. 605 et seq. 



