MICRO-ORGANISMS. 71 



Schutz's Method. 



Sections (and cover-glass preparations) are stained for some 

 hours in Aqueous Solution of Methylene Blue, differentiated 

 in very weak Acetic Acid (J p. c.) dehydrated in Alcohol, 

 cleared in Cedar Oil, and mounted in Balsam. 



SYPHILIS BACILLUS. 



Lusgarten's Method. 



Sections are placed in Gentian-Violet Aniline-Water (p. 

 58) for 12 to 24 hours at the ordinary temperature of the 

 room, then for 2 hours at 40 C. 



The sections are transferred to Absolute Alcohol for a few 

 minutes, then placed for 10 seconds in 1'5 p. c. solution of 

 Permanganate of Potassium, and washed in Sulphurous Acid. 

 If the ground substance of the sections is not completely 

 decolourised, the second part of the process must be repeated. 

 After this the sections are dehydrated, cleared, and mounted 

 in Balsam. 



These bacilli, after staining by the Koch-Erhlich or Ziehl- 

 Neelsen methods (unlike the tubercle bacilli), are easily de- 

 colourised by mineral acids. 



Giacomi's Method. 



Cover-glass preparations are stained for a few minutes in 

 a hot solution of Fuchsine, then placed in Water containing 

 a few drops of solution of Perchloride of Iron; then de- 

 colourised in strong solution of Perchloride of Iron. Some- 

 times a precipitate is formed with the Iron Solution, then the 

 decolourisation is completed in Alcohol. Counterstain with 

 Vesuvine. 



PNEUMO-CQCCUS. 



Gram's Method 



For staining the cocci. 



Sections which have been deeply stained in Gentian- Violet 



