3 * 8 BACTERIOLOGY. 



extremity develops an enlargement, giving the rod 

 the appearance of a pin. The spore formed by the 

 contraction of the plasma in the swollen end finally 

 becomes globular. The vibrios appear in vegetable 

 infusions, causing fermentation of cellulose. 



Genus VI. Clostridium. 



SPECIES. 



ASSOCIATED WITH DISEASE IN ANIMALS : 



Clostridium of symptomatic anthrax Pathogenic. 



UN ASSOCIATED WITH DISEASE : 



Clostridium butyricum . . . Zymogenic saprophytes. 

 Clostridium polymyxa . * . ,, ,, 



Clostridium butyricum, Prazmowski (Bacillus 

 amylobacter. Van Tieghem ; Bacillus butyricus. 

 Bacillus of butyric acid fermentation}. Rods 3 10 

 IJL long, and under i p wide, often indistinguish- 

 able from Bacillus subtilis. They grow out into 

 long, apparently unjointed threads. They are 

 mostly actively motile, but also occur in zoogloea. 

 The rods and threads are sometimes slightly bent 

 like vibrios. They are anaerobic. The shorter rods 

 as a rule swell in the middle, becoming ellipsoidal, 

 lemon or spindle-shaped ; the long rods, and some- 

 times the short ones, swell at one end ; in either 

 case ellipsoidal spores are developed (Fig. 124). 



If they be cultivated in nutrient gelatine, the 

 medium is liquefied, and a scum formed on the 

 surface. They grow best between 35 and 40 C. 

 The spores are widely distributed in nature, and 



