3io 



The " Long Lactic Bacteria." LJ uly > 



is unknown, and it seems doubtful whether they have any 

 role in the ripening of Cheddar cheese comparable to that 

 they are supposed to play in Emmenthaler cheese.* 



They conclude that on account of the wide distribution of 

 this class of organism in dairy produce in America there is 

 always opportunity for the digestive tract of man to become 

 seeded with them ; that there is no evidence that they are 

 found in human faeces except when consumed in large 

 numbers in fermented milks ; that it is evident the organisms 

 do not find a favourable condition for growth in the alimen- 

 tary tract, and will not be an important factor in the intestinal 

 flora of man. 



White and Avery also obtained their cultures of lacto- 

 bacilli from milk only ; and they also came to the conclusion 

 that milk alone is a suitable medium. There are, however, 

 different publications in German literature f which show that 

 the so-called lactobacilli must be common in nature. 



As growth of this type is slow in the media commonly em- 

 ployed in the bacteriological laboratory different workers 

 have attempted from time to time to find a special medium 

 better adapted for the cultivation and isolation of bacteria of 

 this class. Cohendy has found that an extract of malt in the 

 medium is more favourable to their growth. Heinemann and 

 HefTeren,J working at about the same time as White and 

 Avery, and previous to Hastings and Hammer, cultivated 

 them successfully in a special medium of agar containing '5 

 per cent, glacial acetic acid and 2 per cent, glucose. They 

 proved lactobacilli to be present normally in human faeces, 

 faeces of cows and horses, in various fermented and aromatic 

 foods, cattle foods, saliva, normal gastric juice, various fer- 

 mented milks, ordinary market milk, and in soil, manured 

 or unmanured. They believe that these organisms are widely 

 distributed in nature and are identical with B. Bulgaricus, 

 B. Boa-Oppler, B. pants fermentati, and other bacteria sup- 

 posed to belong to the class of acid-producing organisms of 

 the mouth and intestines. This is the same conclusion as that 

 of Lohnis.ll 



* In the manufacture of Emmenthaler cheese, lactobacilli are employed as 

 a starter. 



f See Lohnis's Handbuch der Landwirtsch. Bakteriologie, 1910. 



% Cenlralblatt fiir Balder., Bd. 25, 1909. || Idem, Bd. 18, 1907. 



