296 MANUAL OF BACTERIOLOGY. 



are visible only after about two or three days. It grows on the 

 ordinary media, but according to some authors it does not grow 

 on potato. Milk may or may not be coagulated. The growths 

 are never very luxuriant, and may die out after a few trans- 

 plantations. 



Streptococcus pyogenes longus is not killed with certainty 

 when suspended in normal salt solution and heated at 60° C. 

 for one hour.* The Streptococcus pyogenes occurs frequently 





a 



I-/ 



c 



T 



^-3^ "-V^ 



/ 



Fig. 67.— Streplocaccus pyogenes, from a pure culture. (X looo.) 



on the mucous surfaces of the healthy body. It is often found 

 in pus, especially pus of spreading inflammations of the kind 

 known as celluhtis. This organism is the commonest infectious 

 agent in puerperal fever, metritis and peritonitis. It occurs 

 commonly in inflammations of the serous membranes— pleu- 

 ritis, pericarditis and peritonitis. It has been discovered many 

 times in ulcerative endocarditis and in bronchopneumonia. It 

 is frequently present in the false membrane found in genuine 

 *V. Lingelsheim in KoUe and Wassermann. Bd. III., 1903. p. 318. 



