354 BACILLI OF NO KNOWN PATHOGENIC PROPERTIES. 



limes in an almost epidemic manner, as was the case in 

 1843 in Paris, where it grew more especially in the bread 

 obtained from the military bakehouses. It does not 

 set up any symptoms in the bodies of warm-blooded 

 animals, even when it is injected into the blood in large 

 quantities. 



Comparison 

 with bacillus 

 prodigioeus : 

 higher 

 optimum of 

 temperature. 



Colour more 

 like that of 

 red wax. 



Toxic action 

 on animals. 



Bacillus indicus ruler (Koch). 



This organism was isolated by Koch from the contents 

 of the stomach of a monkey in India; it produces a 

 colouring matter similar to that of bacillus prodigiosus. 

 The organism has the form of fine very short bacilli, 

 with rounded ends. In gelatine plates the deeply placed 

 colonies show under a low power even after 20 hours a 

 golden yellow colour and a wavy outline ; the superficial 

 colonies liquefy the gelatine, and form a funnel-shaped 

 depression, which very soon disappears on account of 

 the rapidly spreading liquefaction. The liquefied gela- 

 tine has a distinctly red colour. The optimum of 

 temperature is higher in the case of bacillus indicus 

 than in the case of bacillus prodigiosus ; while the latter 

 grows best at about 25 C., and as the temperature is 

 increased gradually shows less growth, the bacillus 

 indicus flourishes best at about 35 C. ; hence luxuriant 

 cultivations can be obtained on agar, on which it forms 

 deposits at first of a white colour, but soon assuming a 

 red hue. On potatoes an intensely red layer is formed, 

 the colour of which is more of a wax-red colour, while 

 the colour of the bacillus prodigiosus is darker, with a 

 slight tendency to violet. 



Another important distinction between these two 

 bacilli is that the bacillus indicus is not without effect 

 on animals, but, on the contrary, rapidly kills them 

 when it is injected directly into the blood in large 

 quantities. Rabbits die within 3 to 20 hours, violent 

 diarrhoea setting in a short time after the injection ; on 

 post-mortem examination we find the appearances of a 

 severe gastro-enteritis, at times accompanied with exten- 

 sive ulceration of the intestinal mucous membrane. 



