494 MICRO-ORGANISMS IN WATER 



MICROCOCCUS PLUMOSUS 



Authority. "Bi-&ut\ga,m,DLe Bakterien derNutz- und Trinkwasser,A.([a,metz. 

 Vienna, 1888. 



Where Found. In water. 



Microscopic Appearance. Bound cocci 0'8 /x in diameter, forming zooglcea. 

 Not motile. 



Cultures. 



GELATINE PLATES. Forms tongue-shaped yellowish white colonies, the edges 

 of which are generally raised like a rampart above the surface of the gelatine. 

 No liquefaction takes place. 



GELATINE TUBES. Forms on the surface a slimy expansion, from which 

 ramify delicate white extensions, resembling crystal needles. In the depth 

 similar extensions are visible along the needle's path ; these ramifications con- 

 sist of beaded strings of colonies. 



POTATOES. Forms a yellowish white irregular expansion, with tongue- 

 shaped projections. 



MICROCOGCUS AQUATILIS 



Authority. Bolton, 'Ueber das Verhalten verschiedener Bacterienarten 

 im Trinkwasser,' Zeitschrift f. Hygiene, vol. i., 1886, p. 94. 



Where Found. Very frequently in water. 



Microscopic Appearance. Very small cocci, gathered together in groups. 



Cultures. 



GELATINE PLATES. Forms circular, porcelain- white, smooth, and slightly 

 raised colonies. Under a low power the depth colonies are roundish, with a 

 rough denticulated edge, and resemble a mulberry in shape, and are of a light 

 yellow colour. The surface colonies are circular and smooth-rimmed; the 

 centre is dark, and numerous furrows extend from it, enclosing small rhombic 

 irregular spaces. No liquefaction takes place. 



GELATINE TUBES. Grows on the surface and along the needle's path in the 

 depth, producing a white growth. 



AGAK-AOAK. Forms a white expansion. 



PEDIOCOCCUS ALBUS 



| LIQUEFIES GELATINE | 



Authority. Lindner, Die Sorcine-organismen dcr Guninysgewerbc, Ber- 

 lin, 18HH. 



Where Found. In well-water. 



Microscopic Appearance. -Cocci arranged as diplococci and in tetrads. 

 It does not exhibit the typical sarcina form, but occurs frequently in a pseudo- 

 sarcina form, when the tetrads lying close together become pushed one on the 

 top of the other. 



Cultures. 



GELATINE PLATES. Rapid liquefaction of the gelatine takes place, the ball- 

 shaped colony sinking to the bottom and forming later an irregular flocculent 

 mass. 



GELATIN K Tri;i-:s. In twenty-four hours the whole length of the needle's 

 path in the depth is liquefied, and at the bottom of the canal a white flocculent 

 sediment collects, which on the fourth day assumes a faint orange tone. 



AGAR-AGAR. Forms a broad and dry expansion, which later becomes orange- 

 coloured. 



POTATOES. Forms a dirty white cake-like expansion. 



Remarks. In culture fluids it rapidly forms a pellicle. It grows best at 20 to 25 

 C., but will also develop at 40 C. It will withstand an exposure of twelve minutes 

 to 50 to r>;V C., but an exposure to 00 C. for eight minutes destroys it. 



