164 JOHNKS DISEASE 



do not die, the bacilli being less toxic than Nos. i to 7. 

 The only varieties that produce nodules in the kidney 

 are Tobler I. and Grassberger's bacillus, but the 

 nodules are very few in number. Cultures have been 

 obtained from the urine with Nos. 9 to 11, whilst those 

 made from the urine of animals injected with Nos. 8, 

 12, and 13 have all proved negative. In animals inocu- 

 lated with the fish tubercle bacillus and with Duval's 

 bacillus, caseous nodules have been found in the peri- 

 toneum, but attempts to trace the passage of the 

 bacilli through the kidney by microscopical examina- 

 tion of sections of this organ have all given negative 

 results. 



All the bacilli under consideration are more or less 

 non-toxic if inoculated into the peritoneal cavity or 

 subcutaneously, and the same is true if they are killed 

 by heating and injected intravenously. By the term 

 "non-toxic" is meant that there is no rise of temperature, 

 or loss of appetite or weight, and the animal does not 

 die after the inoculation of 100 to 200 milligrammes of 

 the bacilli. That some of these bacilli are, to a certain 

 degree, pathogenic for animals if inoculated into the 

 peritoneal cavity or subcutaneously, has frequently 

 been demonstrated by many investigators. The lungs 

 of some of the rabbits inoculated subcutaneously with 

 B, phlei have consisted, to a large extent, of necrosed 

 tissue, yet the animals, while alive, appeared to be 

 quite healthy. In one case hardly one-third of the 

 normal lung tissue remained. 



On reviewing the comparative experiments, one is 

 forced to assume that the difference between these 

 acid-fast bacilli is one of degree only ; but in dividing 

 them into groups, toxic and non-toxic, it is clear, from 

 what has already been said, that Johne's bacillus is 

 one of the least toxic of the non-toxic group. When 



