14 PRACTICAL BACTERIOLOGY. 



DEMONSTRATION VI. 



staining of Flagella — Cultures of Bacillus Anthracis. 



Flagella Staining. 

 Ordinary methods of staining do not suffice to 

 demonstrate flagella, so that special staining processes 

 are required. Emulsions in sterile distilled water of 18 

 hour agar cultures of Bacillus typhosus and of Spirillum 

 choleras asiaticae are furnished. 



1. Muir's modification of Pitfield's method. 

 The following re-agents are required: 

 The mordant, 



10% aqueous solution tannic acid, filtered 10 co. 

 Saturated aqueous solution, bichloride 

 of mercury . . . . . . 5 cc. 



Saturated aqueous solution, alum . . 5 cc. 

 Ziehl's carbol-fuchsin . . . . 2 cc. 



This mordant will keep for one or two weeks. 

 The stain, 



Saturated aqueous solution of alum, 



filtered 10 cc. 



Saturated alcoholic solution of gentian 



violet 2 cc. 



This stain will keep two or three days. 

 The cover glasses used must be thoroughly cleansed. 

 This may be easily efiPected by rubbing first with a clean 

 cloth, then washing in a mixture of equal parts of 



