16 BACTERIOLOGY. 



beer and wine, the clotting of milk by bacteria in 

 making cheese, the fermenting of cabbage in making 

 sauerkraut. 

 Pto- It may be well to mention here certain substances 



mames 



that are formed principally in the decomposition of 

 meat and fish by bacteria. They are called ptomaines, 

 and are present in partially decomposed animal and 

 vegetable matter. Some of them are highly poisonous. 

 The most common poisonous ptomaines are those 

 found in partially decomposed meat, fish, and ice-cream. 



