70 GENERAL BACTERIOLOGY LESSON 



(c) Wash in water, and then place in alcohol for half a 

 minute. 



(d) Now float the cover-glass on aniline gentian-violet 

 for five to fifteen minutes, and proceed as described above. 



Examine with high and low powers and -^ in. oil 

 immersion. The central mycelium is stained blue, 

 while the clubs, if present, generally remain 

 unstained or are light yellow. 



(2) Differential staining of dubs and mycelium. 



(a) Fix the sections on clean cover-glasses and dissolve 

 out the paraffin. 



(b) Stain in a 2 per cent aqueous solution of rubine for 

 two hours. 



(c) Wash in water till the sections are dark red. 



(d) Pass quickly through spirit, and then again wash in 

 water till the sections are pink. 



(e) Stain in Loffler's methylene-blue for half a minute 

 to one minute. 



(/) Wash in alcohol till the sections are almost pink 

 again. 



(g) Clear in xylol and mount. 



Examine with a high power or -^ in. oil immersion. 

 The clubs are red and the mycelium blue. 



Paraffin Sections of Pysemic Spleen (Streptococcus) 

 stained by Gram's Method 



(a) Fix and prepare the sections as before. 



