264 MICRO-ORGANISMS AND DISEASE. [CH. xxi. 



Non-pathogenic organisms have a markedly greater resisting power to 

 phenylpropionic and phenylacetic acid and to perchloride of mercury 

 than pathogenic. 



Koch's comma bacilli of Asiatic cholera and Tinkler's comma 

 bacilli behave in this respect like non-pathcgenic organisms. Sporeless 

 non-pathogenic bacilli have a lesser resisting power than non-pathogenic 

 nnicrococci. 



