( 31 ) 



As to the second species, the Lactobacillus "proper of yoghurt, 

 it was troublesome to grow its colonies on milk agar' plates, but 

 on malt extract agar it was mure easily obtained. In literature 

 it has been named Bacillus Massol by GrRiGOROFF, but 1 think that 

 name superfluous as the characters correspond fairly well with those 

 of the kephir bacilli which also occur in our country; for instance, 

 as has been observed before, in yeast and buttermilk. Sown in 

 slightly soured milk this Lactobacillus can produce the strong acid 

 mentioned above, without the help of oilier bacteria. Evolution of 

 carbonic acid does not take place and the product has a very pure 

 taste, although a beginning of fat cleavage seems inevitable at such 

 a high amount of acid. 



Metchnikofh ascribes a very favourable influence to the use of 

 yoghurt, as it diminishes the phenomena of autointoxication starting 

 from the intestinal canal, and he explains this effect by accepting 

 that the Lactobacillus, after passing the stomach, continues active 

 in the intestine, and checks 1 ) the formation of the obnoxious products 

 which derive from other bacteria species. I do not doubt hut this 

 may be brought about by the lactic acid, but I think it highly impro- 

 bable that the presence of the lactic acid bacteria from the yoghurt 

 themselves should be required in the intestine. I think this conclusion 

 is necessary, first because, without the use of yoghurt or other soured 

 milk preparations, there occur in the intestine lactic acid ferments 

 of different species, and second, because the conditions for lactic acid 

 formation by the active ferments are wanting or must at least be 

 very unfavourable there. 



As to the first point I refer to the following experiments. 



If sterile milk is infected with faeces of different origin (man, 

 cattle) and treated as described for the elective culture of Lactococcus, 

 without access of air and repeatedly reinoculated at a temperature 

 between 23° to 26° C, the said genus of microbes is indeed obtained 

 by which as good cream souring can be obtained as with the pure 

 cultures prepared in the before described way. 



If sterile milk is infected in a corresponding way and exposed 

 to the conditions wanted for Lactobacillus, that is, if cultivated in 

 absence of air at 40 to 45° C, a fermentation of coli will first arise 

 and later or simultaneouslv a butyric acid and no lactic acid fermen- 



l ) Quelques remarques sur Ie lait aigri. Rémy, Paris, 1907. In this paper Mf.tchnikoff 

 gives many assertions but no decisive experiments. Besides, li is bacteriological 

 elucidation, p. 26, is not clear. The elaborate and interesting work of Dr. A. Combe, 

 [/autointoxication intestinale, Paris 1907, is neither quite convincing fromamicro- 



biological point of view. 



