318 BACTERIOLOGY. 



After one or two minutes of careful heating the mor- 

 dant is then thoroughly and completely washed off the 

 cover-glass by a jet of water. This can be easily done if 

 the specimen has not been over-heated. If the edge has 

 dried down, it should be loosened with a pin or knife and 

 then washed off. To still farther clean the cover-glass, it 

 may be dipped for a few seconds in absolute alcohol and 

 again washed with water. 



The excess of water is drained from the cover-glass 

 which is then covered with a hot saturated solution of 

 anilin-water fuchsin. The specimen is then gently and 

 slowly heated over the flame for one to two minutes, avoid- 

 ing actual ebullition. It is then heated to boiling for about 

 half a minute, and finally it is thoroughly washed with 

 water and examined with the A inch oil immersion objective. 

 A number of slender flagella can be seen surrounding each 

 cell. 



Summary for staining flagella: 



Dilution cover-glass preparation. 



Dry in air. 



Once through flame. 



Mordant, hot (1 to 2 min.). 



Wash in water (and clean). 



Dip in alcohol (few seconds). 



Rinse in water. 



Anilin-water fuchsin, hot (1 to 2 min.). 



Wash in water and examine. 



Dry in air. 



Mount in balsam. 



The mordant employed is a slight modification of that originally 

 proposed by Loffler. It has the following composition (A. Fischer): 



Dry tannin 2 g. 



Water 20 c.c. 



Ferrous sulphate (1:2) 4 c.c. 



Cone. ale. fuchsin 1 c .c. 



The tannin should be kept in a desiccator. It is dissolved in 

 the stated amount of water by the aid of gentle heat. The two other 



