96 BACTERIOLOGY 



Agar slant and glycerine agar slant. A good growth, which at 37 C. is yellow, 

 and at 22 C. a whitish yellow. 



Blood serum. Growth whitish yellow. 



Potato. Growth glistening, whitish yellow. 



Milk. Not coagulated. 



Bouillon. Turbid, stringy sediment. Media first rendered alkaline, then acid. 

 Indol negative. 



Glucose, lactose, and saccharose bouillon. No gas. 



Pathogenesis . Dogs, rabbits, and guinea pigs negative by subcutaneous, intra- 

 venous, and intraperitoneal injections. 



Habitat. Associated with suppurating processes in cattle. 



6 1. M. subflavus v. Besser 



M. tetragenus-subflavus v. Besser : Ziegler's Beitrage path. Anat., 1889, 331. 



Morphology. Cocci round-oval, medium-sized, in tetrads. Do not grow in 



nutrient gelatin. 

 Agar colonies. Flat, dirty white, glistening, 0.5 mm., with wrinkled margins ; 



microscopically, a small brown nucleus, a grayish brown irregular-striped 



zone, and a wrinkled outer margin. 

 Agar slant. Growth flat, spreading, grayish white ; later, the color of M. 



pyogenes aureus. 

 Potato. Growth pale brown. 

 Habitat. Isolated from nasal mucus. 



CLASS VII. DISTINCTLY CHROMOGENIC. FORMS A PIGMENT ON 

 GELATIN OR AGAR. PIGMENT YELLOWISH-ORANGE. GELATIN 

 LIQUEFIED. 



I. Typical gonococcoid forms. 



62. M. epidermis. 



H. Sarcina, or typical tetrad grouping of the elements. 



63. M. albus (Lindner). 



III. Staphlococcus grouping of the elements. 



A. Gelatin liquefied along the length of the stab, or to a considerable 



depth. 

 I. Gelatin rapidly liquefied. 



64. M. pyogenes var. aureus Rosenbach. 



65. M. aureus Dyar. / 



66. M.flavus Flligge. 



