306 BACTERIOLOGY. 



cow's milk, producing a blue colour. It has been 

 observed, especially in the north of Germany, 

 during the warm months ; and where milk is 

 kept in hot rooms, in the winter also. The blueing 

 was originally attributed to a diseased condition 

 of the cows, or to their eating certain meadow 

 plants. 



Bacillus acidi lactici. Long and short rods, 

 i 2'S p, long, '3 *4 /x thick, and thread-forms; no 

 cocci ; spore-formation.* Cultivated on nutrient 

 gelatine the breadth of the rods is lessened. They 

 grow best between 35 and 42 C., and cease under 

 ioC. Cultivated at a temperature over 45*5, they 

 are no longer able to produce acidity. Probably 

 several micro-organisms are able to produce an 

 acid reaction in milk. 



They occur with various other bacteria in sour 

 milk, and a pure cultivation, isolated by plate- 

 cultivations, turns sterilised milk sour. 



Bacillus Fitzianus, Zopf. Cocci, short rods, 

 long rods, and threads. This bacillus, cultivated 

 in meat extract and glycerine at 36 C., causes an 

 active fermentation with the production of ethyl 

 alcohol. Spore-formation occurs in the rods. 

 Observed in unboiled hay infusion, accompanying 

 the hay bacillus. 



Bacillus subtilis (Hay bacillus}. Cylindrical 

 rods as much as 6 /x, in length, and about three 

 times as long as broad. Single forms grow to 



* Hueppe, Mittheil a.d. Gestindheitsamt> N. Band. 



