YC 88491 



GRAM'S METHOD OF STAINING. 



1. Prepare even thin film and fix. 



2. Aniline gentian violet, -2 to 5 minutes. 



3. Gram's iodine solution, i to 2 minutes. (Tea-leaf color.) 



4. Wash in water and decolorize with 95% alcohol. 



5. Wash in water and counterstain with Bismarck brown or 

 with dilute carbol fuchsin. 



6. Wash, dry and mount. 



Practically all pathogenic cocci are Gram positive, except the 

 Gonococcus, the Meningococcus, the M. catarrhalis and the M. 

 melitensis. 



Practically all pathogenic bacilli are Gram negative, except the 

 e pore-bearing ones (exception B. malig. cedemat.), the acid-fast ones 

 and diphtheria and diphtheroid organisms. 





