350 BACTERIOLOGY 



2. Grow on ordinary nutrient gelatin. SWINE ERYSIPELAS GROUP. 



a. Stain by Gram's method. 



5. Mycobact. rhusiopathicz (Kitt). 



6. Mycobact. murisepticum (Flligge). 



b. Not stained by Gram's method. 



7. Mycobact. malei (Lb'ffler) Migula. 



B. Cells commonly irregularly swollen, or clavate cuneate ; rarely show 

 branched forms. DIPHTHERIA GROUP. 



1. On Lbffler's blood serum a decided yellow growth. 



8. Mycobact. lac t is. 



2. On Lbffler's blood serum growth whitish, not pigmented. 



a. Stain by Gram's method. 



9. Mycobact. diphtheria (Klebs). 



10. Mycobact. pseudodiphthericum (Kruse). 



1 1 . Mycobact. pseudotuberculosis (Kutscher) . 



b. Do not stain by Gram's method. 



12. Mycobact. hastilis (Seitz). 



II. Not stained with aqueous solutions of basic aniline colors ; not easily de- 

 colorized by mineral acids when stained with Ziehl's carbol fuchsin. 



TUBERCLE GROUP. 



A. Do not grow in nutrient gelatin at room temperatures. 



1. Not decolorized by alcohol when stained with Ziehl's carbol fuchsin. 



a. Growth on glycerin agar slow, dry, rough, warty, or fragmented. 



13. Mycobact. tuberculosis. 



b. Growth on glycerin agar visible in about 8 days ; at 37, flatter 



and more watery. 



14. Mycobact. avium. 



2. Decolorized by alcohol when stained with Ziehl's carbol fuchsin. 



15. Mycobact. smegmatis. 



B. Grow at least feebly in nutrient gelatin at room temperatures. 



p. Growth on agar or glycerin agar becomes a deep yellowish or orange. 



1 6. Mycobact. butyri. 



2. Growth on agar or glycerin agar whitish, or only a pale yellow. 



a. On the surface of bouillon a yellowish membrane. 



17. Mycobact. Mo'elleri. 



b. On the surface of bouillon a whitish membrane. 

 * No odor in bouillon cultures. 



1 8. Mycobact. graminis. 



** Bouillon cultures have a bad odor. 



19. Mycobact . friburgensis (Korn). 



