NON-PATHOGENIC MICROCOCCI. 615 



222. PEDIOCOCCUS ACIDI LACTICI (Lindner). 



Found by Lindner in mash from malt and in hay infusion. 



Morphology. Micrococci, from 0.6 to 1 M in diameter, solitary, in pairs, 

 or in tetrads division in two directions. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying micrococcus. Grows very slowly in the usual culture media at 

 the room temperature. Upon gelatin plates small colonies are developed, 

 which are first colorless and later yellowish-brown. In agar stick cultures 

 a moist, thin, colorless layer is slowly developed upon the surface. Upon 

 potato a scanty, scarcely visible growth. Lactic acid is produced by the 

 growth of this tetragenus in saccharine solutions. 



223. PEDIOCOCCUS CEREVISIJE (Balcke). 



Found in beer and in the air of breweries. 



Morphology. Micrococci, solitary, in pairs, or in tetrads. 



Biological Characters^ An aerobic and facultative anaerobic, non- 

 liquefying micrococcus. Grows slowly in the usual culture media at the 

 room temperature. Is killed by a temperature of 60 C. maintained for 

 eight minutes. Upon gelatin plates forms small, colorless colonies, which 

 later are yellowish-brown. In gelatin stick cultures a white, leaf- like layer 

 is formed on the surface and a grayish-white growth along the line of punc- 

 ture. Upon agar a moist, grayish-white, iridescent layer with smooth mar- 

 gins. Upon potato a scanty, scarcely visible growth. 



224. MICROCOCCUS TETRAGENUS MOBILIS VENTRICULI (Mendoza). 



Found in the contents of the stomach. 



Morphology. Micrococci, in tetrads, enclosed in a transparent capsule. 



Biological Characters. An aerobic, non-liquefying, motile (?) tetrage- 

 nus. Grows slowly in the usual culture media at the room temperature. 

 Upon gelatin plates forms superficial colonies which are circular in outline, 

 with well-defined margins, and dirty -white in color ; under a low power they 

 are seen to be finely granular, both on the surface and in the interior. In 

 gelatin stick cultures grows upon the surface as a dirty-white layer ; old 

 cultures have a " sugar color " and give off an odor like that of skatol. The 

 growth upon agar is similar to that upon gelatin. 



225. MICROCOCCUS TETRAGENUS SUBPLAVUS (Von BeSSer). 



Found in nasal mucus. 



Morphology. Spherical or oval cocci of medium size, usually associated 

 in tetrads. 



Biological Characters. An aerobic and facultative anaerobic tetra- 

 genus. Does not grow in nutrient gelatin. Grows at the room temperature 

 in nutrient agar. Upon agar plates forms flat, dirty -white colonies, 0.5 

 cubic centimetre in diameter, with shining surface and somewhat wrinkled 

 margins ; under a low power these are seen to have a small brown nucleus 

 surrounded by a grayish-brown, irregularly striped zone, around which is a 

 wrinkled margin. The deep colonies are dark-green and punctiform, of very 

 irregular form. Upon the surface of agar a broad, flat, grayish-white layer 

 is formed, which in three or four days commences to turn brown at the mar- 

 gins, and at the end of four weeks has the color of cultures of Staphylococcus 

 Eyogenes aureus. Upon potato a pale-brown layer is developed along the 

 ne of inoculation. 



226. SARCINA AURANTIACA. 



Found in the air and in water. 



Morphology. Micrococci, in pairs, with hemispherical elements, in tetrads,. 



