32 GENERAL BACTERIOLOGY LESSON 



(li) Now counterstain with Loffler's methylene-blue, wash 

 in water, dry and mount. 



Examine with ^ m - ^ immersion : the bacilli are 

 blue and the spores red. 



Make a drawing. 



The spores of the Bacillus filamentosus and the 

 Bacillus megatherium are more easily stained than 

 those of the Bacillus anthracis. 



Second Method. 



(a) Prepare a film in the usual manner. 



(b) Pass it three times through the flame. 



(c) Place it for two minutes in absolute alcohol, and for 

 further two minutes in chloroform. 



(d) Wash the film in water, dry it between blotting- 

 paper, and pass it again three times through the flame. 



(e) Leave it for two minutes in a 5 per cent solution of 

 chromic acid, and then wash it in water, and dry it between 

 blotting-paper. 



(/) Once more pass it three times through the flame, and 

 place it in a warm solution of carbol fuchsine for five to 

 fifteen minutes. 



(g) Einse the film in water, and decolourise in 5 per cent 

 sulphuric acid, till the specimen is faintly pink. 



(ti) Wash it in water and counterstain in malachite 

 green. 



(i) Wash again, dry and mount. 



The spores are red and well stained, the bacilli green. 



