H 



PRACTICAL BACTERIOLOGY. 



il Prepare cover glass film~ from the gelatine culture 

 of Streptococcus pyogenes, and also from the liquefying 

 gelatine culture of Staphylococcus pyogenes aureus. 

 Stain them according to (xram's method as follows: 



{(i) Place the films in alcohol one to two minutes. 



(/>) Without drying, transfer to anilin gentian violet 

 for two minutes. 



(c) Rinse in water or .6% saline solution, and then 

 place for one-half to one minute in Gram's iodine solu- 

 tion, (Iodine 1 part, Potassium iodide 2 parts, Water 

 300 parts). 



{(I) Rinse in water, end then in alcohol, till no more 

 stain comes away. 



(e) Wash in water, dry and mount in Canada balsam. 



