526 A MANUAL OF BACTERIOLOGY 



Anaerobic Butyric Acid Bacteria 



Anaerobic organisms occur in milk, in which they produce a 

 marked butyric acid fermentation with changes like those of the 

 B. perfringens. Such are the B. butyricus (Vibrion butyrique, 

 Pasteur), Clostridium butyricum (Prazmowski), and Bacillus 

 amylobacter (Van Tieghem), which are not clearly distinguished 

 from one another. They form short and long rods and filamentous 

 forms, which are Gram -positive. Spores are small and oval, 

 central, sub-terminal, and frequently clostridial. Milk is rapidly 

 acidified and curdled. They do not liquefy gelatin nor blacken 

 meat broth, which is acidified. The surface colonies are smooth, 

 the deep ones filamentous. They are non-pathogenic. 



