FAMILY X. LACTOBACILLACEAE 511 



from arginine (exceptions in Streptococcus mitis). Not beta hemolytic. No growth in 6.5 

 per cent NaCl broth, at pH 9.6 or in 0.1 per cent methylene blue milk. No reduction of 

 litmus before curdling milk. Tyrosine not decarbo.xylated. 



A. No growth at 50° C. Growth in 2 per cent NaCl broth. 



1. Starch not hydrolyzed. No growth on 40 per cent bile blood agar. 



a. Indifferent (gamma hemolytic) on blood agar. Raffinose and inulin fer- 

 mented. Large, mucoid colonies produced on 5 per cent sucrose and raffinose 

 agar. 



10. Streptococcus salivarius 



aa. Greening (alpha hemolytic) on blood agar. Inulin not fermented. Raffinose 

 may or may not be fermented. Mucoid colonies not produced on 5 per cent 

 sucrose agar. 



11. Streptococcus mitis. 



2. Starch hydrolyzed. Growth on 40 per cent bile blood agar. 



a. Lactose fermented. 



12. Streptococcus hovis. 

 aa. Lactose not fermented. 



13. Streptococcus equinus. 



B. Growth at 50° C. No growth in 2 per cent NaCl broth. 



14. Streptococcus thermophilus. 

 III. Growth at 10° and 45° C. Ammonia produced from arginine. 



A. No growth in 6.5 per cent NaCl broth, at pH 9.6 or in 0.1 per cent methylene blue 

 milk. Tyrosine not decarboxylated. Not hemolytic. Litmus milk not reduced be- 

 fore curdling. 



15. Streptococcus iiheris. 



The Enterococcus Group 



B. Growth in 6.5 per cent NaCl broth, at pH 9.6 and in 0.1 per cent methylene blue 

 milk. Tyrosine decarboxylated. Lancefield group D. 



1. Not beta hemolytic. 



a. Gelatin not liquefied, 

 aa. Gelatin liquefied. 



16. Streptococcus faecalis. 



16a. Streptococcus faecalis var. liquefaciens. 



2. Beta hemolytic. 



a. Mannitol and sorbitol fermented. Litmus reduced before curdling milk. 

 May or may not liquefy gelatin. 



16b. Streptococcus faecalis var. zymogenes. 

 aa. Mannitol and sorbitol not fermented. Litmus not reduced before curdling 

 milk. Gelatin not liquefied. 



17. Streptococcus durans. 



The Lactic Group 



IV. Growth at 10° but not at 45° C. No growth in 6.5 per cent NaCI broth or at pH 9.6. 

 Tjnosine not decarboxylated. Growth in 0.1 per cent methylene blue milk; reduces 

 litmus before curdling milk. Not hemolytic. Lancefield group N. 



A. Growth at 40° C, in 4 per cent NaCl broth, at pH 9.2 and in 0.3 per cent methylene 

 blue milk. Produces ammonia from arginine. Maltose fermented. 



18. Streptococcus lactis. 



B. No growth at 40° C, in 4 per cent NaCl broth, at pH 9!2 or in 0.3 per cent methylene 

 blue milk. Ammonia not produced from arginine. Maltose usually not fermented. 



19. Streptococcus cremoris. 



