THE STAINING OF BACTERIA IN SECTIONS 103 



Bismarck brown cannot be used, but only the so-called 

 pararosanilines, to which class belong methyl violet, gentian 

 violet, Victoria blue, etc., the strong affinity which these 

 colouring matters have for iodine being, according to 

 Unna, the cause of the remarkable action of Gram's 

 method. 



