BACILLI 439 



BACILLUS ERYTHROSPORUS 



Authority. Eidam, Cohn's Beilrdge zur Biologic der Pflanzen, vol. iii. 

 p. 128. Miigge, Die Mikroorganismen, 1886, p. 288. 



Where Found. Found originally in putrefying liquids by Eidam, later by 

 Cohn and Miflet ; more recently in drinking-water by Bolton (Zeitschrift f. 

 Hygiene, vol. i., 188fi) and by Migula (Zeitschrift /. Hygiene, vol. viii., 1890, 

 p. 357). 



Microscopic Appearance. Slender bacillus with rounded ends ; forms also 

 short threads. It is very motile. From two to eight oval-shaped spores appear 

 at the ordinary temperature in each rod ; they sometimes extend beyond the 

 wall of the bacillus, and are characterised further by their distinctly dirty red 

 colour. Even when the bacillus is stained with methylene blue, the spores retain 

 their reddish colour. 



Cultures. 



GELATINE PLATES. Forms white centres, which under a low power are seen 

 to have a sharply-defined but irregular edge. The brown central portion is 

 surrounded by a brighter greenish yellow zone. On the surface, after the colony 

 has expanded, distinct wavy lines are seen to radiate from the centre to the 

 periphery, which becomes much lobulated and serrated. A green fluorescence 

 surrounds each colony. The gelatine is not liquefied. 



GELATINE TUBES. Grows abundantly, both on the surface and along the 

 needle's path in the depth, and the whole tube gradually assumes a green 

 fluorescent colour. 



POTATOES. Produces a restricted growth, at first reddish but later nut-brown 

 in colour. 



BACILLUS LATERICEUS ( ' Ziegelrother Bacillus ' ) 



Authority. Adametz and Wichmann, Die Bakterien der Nutz- und 

 Trinkwdsser, Vienna, 1888. 



Where Found. In water. 



Microscopic Appearance. A bacillus three to five times as long as broad, 

 forming short, often bent threads. It is not motile. 



Cultures. 



GELATINE PLATES. Small dot-shaped sealing-wax-red colonies, which under 

 a low power appear circular, finely granular, and of a brown-red colour. The 

 centre is dark and is surrounded by a lighter peripheral zone. No liquefaction 

 takes place. 



GELATINE TUBES. Forms a raised, slimy and sealing-wax-red expansion, and 

 grows but slightly in the depth. 



POTATOES. Expansion of sealing-wax-red colour. 



