496 MICROORGANISMS IX WATER 



MICKOCOCCUS CINNABAREUS 



Authority. Fliigge, Die Mikroorganismcn, 1886, p. 174. 



Where Found. In air and water. 



Microscopic Appearance. Large round cocci ; occurs often as diplococci, 

 but each half is perfectly round ; it often hangs together in threes and fours. 



Cultures. 



GELATINE PLATES. It grows very slowly, the colonies in the depth after four 

 days are only just visible as dots. In about eight days the surface colonies are 

 raised like buttons above the surface of the gelatine. They are at first of a 

 bright sealing-wax-red colour, but later become vermilion. Under a low power 

 the smallest colonies in the depth are lentil-shaped, smooth-rimmed, and of a 

 dark brown red colour. The surface colonies are light brown, transparent at 

 the periphery, circular, but with some irregularities in the periphery. No lique- 

 faction takes place. 



GELATINE TUBES. After from four to five days isolated white colonies are 

 visible in the depth, whilst a moderately-sized button-shaped growth forms 

 on the surface, at first pink but later vermilion in colour. 



POTATOES. Grows very slowly, producing a vermilion expansion. 



MICKOCOCCUS CAKNEUS 



Authority. Zirnmermann, Die Baktericn unscrer Trink- und Nutzwasser, 

 insbcsondcre des Wasscrs der Chcmnitzer Waxxerlcitung, Chemnitz, 1890. 



Where Found. In the Chemnitz water supply. 



Microscopic Appearance. Medium-sized coccus arranged in groups like 

 grapes. The individual cells are on an average 0*83 /JL. It is not motile. 



Cultures. 



GELATINE PLATES. The colonies in the depth are small grey white centres : 

 on the surface they are greyish or pale red, slightly raised and circular expansions. 

 Tinier a low power the rim is at first smooth and the colony is of a uniform 

 greyish red colour. Later the centre becomes darker and is surrounded by a 

 lighter circular zone, which is again encircled by a still lighter zone. In older 

 cultures these bands are not so distinctly marked. No liquefaction takes place. 



GELATINE TUBES. Forms a thin, irregular, circular pale red expansion, 

 which is only slightly raised above the surface of the gelatine. In the depth 

 the needle track is marked by a fine white granular growth. 



AGAR-AGAR. Forms a deep flesh-coloured expansion with a play of violet. 

 The edge is lobular and serrated. 



POTATOES. Grows abundantly, producing a fine red-lead coloured expansion, 

 which is shining at first, but becomes dull later. 



Remarks It grows best at 20 to 22 C., and only very scantily at 30 to 33 C. 



