82 BACTERIOLOGICAL, EXAMINATION OF MILK. 



sodium hydrate .and a few drops of diluted copper sul- 

 phate solution, it produces a violet to a rose-red color, the 

 reaction for peptones (biuret reaction). 



So-called '■'■foison milk,'''' which acts like alkaloids 

 upon animal organisms, is probably due to the presence 

 of ptomaines or toxins produced by bacteria from the 

 albuminoids of the milk. 



To obviate the above described milk anomalies, which 

 are mostly the results of insufficient cleanliness, the stalls 

 must be thoroughly cleaned with water, the walls fre- 

 quently white-washed, all utensils boiled, the udder care- 

 fully washed with warm boiled water and the persons en- 

 trusted with the milking must exercise perfect cleanli- 

 ness. 



Of the numerous micro-organisms contained in nearly 

 all milk, the peptonizing species, the so-called bacteria 

 of bitter milk, "Hueppe's" demand special attention. To 

 this class belong a number of strongly anaerobic and 12 

 facultative anaerobic species, recently described by 

 Fluegge. Under these, according to Fluegge, probably 

 come Bacillus mesentericus fuscus and vulgaris. Bacillus 

 liodermis. Bacillus albus lactis Loeffler, Bacillus butyri- 

 cus Hueppe and Botkin, the bacteria of Duclaux, the 

 Kreuger bacillus, Proteus vulgaris. Micrococcus Conn, 

 Clostridium foetidum -and butyricum. Bacillus mus- 

 coides Liborius, and four varieties called by Ster- 

 ling, bacterium lactis peptonaus. Fluegge has re- 

 cently published the results of a study of the 

 bacteria which peptonize milk, or rather the casein 

 of milk and which for the largest part belong 

 to the group of hay and potato bacilli. He has also called 

 attention to their dangerous character. These bacteria are 

 characterized by forming spores which have extraordi- 

 nary powers of resistance and which are killed only when 

 exposed for two hours to the influence of steam at 100 de- 



