43 2 



BACTERIOLOGICAL ANALYSES 



ANALYTICAL SCHEME FOR ISOLATION OF MEMBERS OF THE COLI AND 

 TYPHOID GROUPS. 



Nutrose agar. 



Red colonies. 

 Escherich group. 



Blue colonies. 

 Gaertner and Eberth groups. 



Lactose peptone solution. 



Gas. 



! 



B. coli communis and its allies. 



I 



Acid and gas in glucrse peptone solution. 



Acid and coagulation in 1 milk. 



General turbidity and indol in bouillon. 



I 

 No gas. 



Gaertner and Eberth groups. 



Glucose peptone solution. 



B. Streptococci. 



19. Pick off streptococcus colonies and subcultivate 

 upon nutrient agar exactly as directed in steps 14, 15 

 and 1 6. 



20. Differentiate the streptococci isolated into mem- 

 bers of the saprophytic group of short-chained cocci, 

 or members of the parasitic (pathogenic) group of 

 long-chained cocci, by means of their cultural charac- 

 ters, and record their numerical frequency in the 

 manner indicated for the members of the coli-typhoid 

 group. 



