NON-PATHOGENIC MICROCOCCI. 599 



3.5 millimetres in diameter, is developed upon the surface, and a finely 

 granular, white growth along the line of puncture. Upon the surface of 

 gelatin a flesh-red layer, which later acquires a violet hue, is formed along 

 the impfstrich. Upon agar the growth is similar but more abundant, and 

 the margins are coarsely toothed. Upon potato an abundant red layer is de- 

 veloped. 



176. MICROCOCCUS CINNABAREUS (Flligge). 



Found in air and in water. 



Morphology. Large, spherical cocci, frequently associated in pairs or in 

 tetrads. 



Biological Characters. An aerobic, non-liquefying, chromogenic mi- 

 crococcus. Grows in the usual culture media at the room temperature. 

 Upon gelatin plates the deep colonies are first seen as minute points at the 

 end of four days ; under a low power they are seen to be oval or lenticular, 

 with a well-defined contour and of a dark reddish-brown color. The super- 

 ficial colonies, at the end of four days, are from 0. 5 to 1 millimetre in dia- 

 meter and brick- red ; at the end of eight days they project from the gelatin in 

 button-shape and are cinnabar-red. In gelatin stick cultures isolated white 

 colonies are seen along the line of puncture at the end of four to five days, 

 and upon the surface a button-like mass of moderate dimensions is de- 

 veloped, which is first pink and later cinnabar-red. Upon potato a cinnabar- 

 red layer is slowly developed. 



177. MICROCOCCUS CEREUS ALBTis (Passet). 



Obtained by Passet (1885) in the pus of acute abscesses (two cases out of 

 thirty-three examined), and by Tils (1890) from the Freiburg water supply. 



Morphology. Large cocci, *1. 16 n in diameter, solitary or associated in 

 irregular groups. 



Biological Characters. An aerobic, non-liquefying micrococcus. 

 Grows in the usual culture media at the room temperature. Upon gelatin 

 plates forms superficial colonies, which attain a diameter of one to two mil- 

 limetres and resemble drops of stearin or white wax. In gelatin stick cul- 

 tures grows upon the. surface as a grayish- white layer with irregular, thick- 

 ened margins, resembling a drop of stearin; scanty growth along the line of 

 puncture. Upon potato a dirty-white layer of moderate thickness is de- 

 veloped. 



178. MICROCOCCUS CEREUS FLAVus (Passet). 



Obtained by Passet (1885), in a single case out of thirty-three examined, 

 from the pus of an acute abscess. 



Morphology. Micrococci of irregular dimensions, associated in irregular 

 groups and occasionally in chains. 



Biological Characters. An aerobic, non-liquefying, chromogenic micro- 

 coccus. Grows in the usual culture media at the room temperature. Upon 

 gelatin plates lemon-yellow colonies are developed, which attain a diameter 

 of one to two millimetres. In gelatin stick cultures the, growth around the 

 point of inoculation resembles a drop of stearin or wax with elevated mar- 

 gins and has a yellow color ; a scanty yellow streak is developed along the 

 line of puncture. Upon potato a citron-yellow layer is formed. 



179. MICROCOCCUS CITREUS. 



Synonym. Cremefarbiger micrococcus (List). 

 Found in water. 



Morphology. Large, spherical cocci, from 1.5 to 2.2/*in diameter, soli- 

 .ary, in pairs, or in chains of eight or more elements. 



Biological Characters. Anaerobic, non-liquefying, chromogenic micro- 



