STREPTOCOCCUS PYOGENES 53 



organisms and with the method and seat of the 

 inoculation. Subcutaneously inoculated, it may give 

 rise to an erysipelatous inflammation, and the 

 organisms are found filling the lymphatics at the 

 margin of the inflamed patch ; or it may give rise 

 to a localised abscess or a spreading cellulitis. In- 

 jected intravenously, it gives rise to an acute septi- 

 caemia, with a blocking of the capillaries of the 

 internal organs with microbes. If certain conditions 

 are associated with the injections, pyaemia results, 

 and the secondary abscesses themselves contain the 

 streptococcus. 



By successive passages through animals and cul- 

 tures in the serum-bouillon media mentioned above 

 organisms of extreme virulence may be obtained. 

 By injections of graduated doses a condition of 

 resistance may be established in animals, and there 

 appears to be some ground for believing that the 

 serum of such protected animals may itself protect 

 other animals from streptococcic infection. 



