168 BACTERIOLOGY. 



arranged in chains ; and stains by Gram's 

 method. According to its virulence the Strep- 

 tococcus produces simple or bullate erysipelas 

 of the skin, suppuration of various organs, and 

 also acute lung inflammations, of an erysipe- 

 latous and spreading character, and acute 

 puerperal fever. The same Streptococcus pro- 

 duces also acute anginas with diphtheritic in- 

 crustations, and the diphtheria-like affection 

 which attacks a patient recovering from scarlet 

 fever. The streptococci found in the so-called 

 frambcesia, a skin disease of the tropics, are 

 certainly not the cause of the disease, and are 

 probably only erysipelas cocci that have pene- 

 trated the skin at the injured places. 



In association with the process of caries or 

 decay of the teeth are found all possible kinds 

 of pyogenic germs. According to Miller the 

 enamel of the teeth is first attacked by acids 

 which are formed in the mouth as the result of 

 bacterial decompositions and then the pyogenic 

 bacteria in the mouth penetrate into the decalci- 

 fied organic substance of the tooth. If cavities 

 are created in this way then it is possible 

 that other microbes, as for example those of 

 tuberculosis and actinomycosis, may enter the 

 body by way of the decayed teeth. 



If we consider the great fluctuations in vir- 

 ulence shown by the pyogenic staphylococci 



