CHAPTER XVIII 



STREPTOCOCCUS INFECTIONS 



THE Streptococcus pyogenes 1 was observed by Koch 

 and, independently, also by Ogston in 1882, but was first 

 isolated by Fehleisen in 1883. The cocci are spheric or 



Fig. 34. Streptococcus pyogenes, from the pus taken from an ab- 

 scess; X1000 (Frankel and Pfeiffer). 



oval, and occur in chains of eight, ten, twenty, or more 

 individuals, though often merely in pairs. They stain 

 readily with the ordinary stains, and retain the color 



1 Pyogenes means " pus producer." 



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