360 BACILLI OF NO KNOWN PATHOGENIC PROPERTIES. 



but without liquefaction and without staining of the 

 gelatine. It occurs very frequently as an impurity on 

 plate cultivations, &c. 



Brown 

 bacillus. 



Bacillus fuscus.* 

 (Bacterium brunneum.) 



This organism was obtained by Schroter from a 

 putrefying infusion of maize in the form of mobile rods, 

 which produced a brown colouring matter, and which 

 he described under the name of bacterium brunneum. 

 These organisms are probably identical with a bacillus 

 which also furnishes a brown colour, and which occurred 

 in some rare cases as accidental impurities in Gottingen. 

 These organisms present the form of long narrow rods 

 with abrupt ends, and irregular and in parts slightly 

 projecting outlines. They form on gelatine plates 

 fairly quickly growing knob -like colonies of a brownish 

 colour ; under a low power we see in the centre 

 irregular brownish-black balls which are surrounded by 

 a highly refracting border. In puncture cultivations 

 their growth is not very characteristic ; on the surface 

 they form a fairly thick, and at a later period a wrinkled 

 brownish-red deposit around the point of entrance of the 

 needle. 



Bacillus of 

 yellow milk. 



Bacillus synxanthus. 

 (Bacterium synxanthum, Ehrenberg.) 



These are actively moving rods which were observed 

 by Schroter t in milk which had accidentally become 

 yellow; by inoculating the organism on normal boiled 

 milk, its colour became citron-yellow. The colouring 

 matter was soluble in water, insoluble in alcohol and 

 ether ; acids decolourised it, alkalies again brought back 

 the colour. Nothing further is known as regards the 

 micro-organisms which produce these effects. 



* Gottinger hyg. Institut. 



f Cohn's Beitr. zur Biol. d. Pflanzen, vol. i., part 2, p. 120. 



