PLATE I. 

 Streptococcus pyogenes. Rosenbach. 



I. Agar streak culture, ten days at 37°. 

 II. Gelatin stab culture, six days at 22°. So vigorous 

 a growth does not often occur. 



III. Agar stab culture, six days at 37°. Stab canal. 



IV. Agar stab culture, six days at 37°. Surface growth. 

 V. Gelatin plate, six days at 22°. 



VI. Gelatin plate, six days at 22°. X 70. Somewhat 

 abnormal form with irregular borders. The larger colonies 

 are superficial; the smaller, deep. 



VII. Gelatin plate, six days at 22°. X 70. Common 

 form. The upper, superficial; the lower, deep. 



VIII. Agar plate, eight days at 37°. X 50. Larger colony 

 superficial; smaller colonies, deep. 



IX. Microscopic preparation from a two days' bouillon 

 culture at 37°. X 700. The individual cocci are usually 

 more regularly round. 



X. Microscopic preparation from a two days' agar 

 culture. Shorter chains. X 1000. 



XI. Microscopic preparation, designated Streptococcus 

 conglomeratus. Smear preparation from the blood of the 

 spleen from a case of scarlatina. Copied from Kurth 

 (Kaiserl. Gesundheitsamt., Bd. vii, cfr. xv, 6 and 8). 



XII. Chains of streptococci, before and during division. 

 Highly magnified. 



t 



XII. 



