SPECIAL STAINING METHODS 661 



1. Stain with a 2 per cent, aqueous solution of methyl blue, 

 three minutes. 



2. Rinse in water. 



3. Stain in a 1 per cent, aqueous solution of safranin, five 

 minutes. 



4. Wash in water. 



5. Differentiate and dehydrate quickly in absolute alcohol, till 

 the sections become again blue. 



6. Clear and mount. 



This method gives a permanent stain which yields excellent 

 results with certain tissues e. g., the skin. 



Other nuclear and cytoplasmic dyes may be combined in a simi- 

 lar manner to the above methods. 



SPECIAL STAINING METHODS 



Iron Hematoxylin (Heidenhain) : 



I. Mordant: 



Ferric alum (violet crystals) 2 grin. 



Distilled water. 100 cc. 



II. Stain: 



Hematoxylin 1 grm. 



95 per cent, alcohol 10 cc. 



Distilled water 100 cc. 



1. Mordant the sections one-half to two hours in I. 



2. Rinse in water. 



3. Stain ten to thirty minutes in II. 



4. Wash well in water. The sections should become very black ; 

 a drop or two of ammonia to one-half litre of water often improves 

 the color. 



5. Decolorize in the mordant, watching each section, and stop- 

 ping the decolorization at the proper time by 



6. Wash thoroughly in slowly running water, or in several 

 changes of still water. 



7. Counter-stain if desired, dehydrate, clear, and mount. 

 This method gives an excellent stain for the finer nuclear struc- 

 ture, mitosis, etc. 



Muchematein (Mayer) : 



Hematein (Griibler's) 0.2 grm. 



Glycerin 40 cc. 



Aluminum chlorid 0.1 grm. 



Distilled water. . . 60 cc. 



