( 2é ) 



Without attributing a special value to this classification I yet wish 

 to keep to it as I think that the facts to be mentioned are fairly 

 well comprised thereby. 



The longusgroup is characterised by its not acting on maltose, 

 so that in maltextract no, or very little acid it formed, but it does 

 decompose milksugar. In milk the forms of this group, if grown 

 after a previous culture of Lactococcus which has produced 5 to 8 c.c. 

 of lactic acid per 100 c.c. of milk, will once more produce a certain, 

 •even a like quantity of acid so that ca. 16 c.c. may be titrated, the 

 latter amount being however an exception. Generally no evolution of 

 carbonic acid is observed but sometimes it is, and then so much gas 

 can arise that a milk beverage is acquired foaming like champagne. 



By a series of transitions, the longus forms obtained at 40° C, 

 are joined with lactobacilli which at a lower temperature find their 

 optimal vital conditions, but which are rarer in milk. 



The caucasicus group comprises those lactobacilli, which are able, 

 independently of lactococci to produce in milk a very high acid 

 formation. At 37 to 40° C. it is possible after three days of their 

 action to titrate 20 to 25 c.c. of normal acid per 100 c.c. of milk. 

 When that amount is reached further acid formation stops. In this 

 case, too, there is a parallel form which, beside much lactic acid, 

 also evolves carbonic acid. What by-product is then formed from 

 the lactose molecule beside the carbonic acid is not yet clear; pro- 

 bably it is aethylalkohol. G. Bertrand has proved that these ferments 

 can produce succinic acid. They greatly owe their notoriety to their 

 presence in kephir, which subject 1 have touched before 1 ). Later 

 however I have come to the conclusion s ) that their distribution is 

 by no means restricted to kephir only, but that they also occur in 

 our climate, sometimes in buttermilk, in cheese and even in common 

 baker's yeast. 



6. Yoghurt ami maya. 



The use of soured milk as drink and food is so familiar to many 

 Eastern countries, and dates from so remote an antiquity that there 

 can be no doubt as to its favourable effect on health, and the esta- 

 blishment of various societies which try to popularise new preparations 

 of that nature, seems to prove that the attention of the Western 

 nations begins to be drawn towards it. 



Both in the preparations of the Eastern nations and in those of 



') Sur le Kefyr. Archives Néerlandaises. T. 23, p. 428, 1891. 

 *) Ferments lactiques de l'industrie 1. c. 



