STAINING 755 



continue the stain for five minutes, or until satisfactorily differentiated. 



3. Wash with distilled water. 



4. Dry and mount. 



The Giemsa and tlie Wright blood stains (other modifications of the 

 original Romanowsky stain) may be used for the same purposes, and 

 are applied in a similar manner. 



Eosin and Methyl Blue Mixture (Mann) : 



1 per cent, aqueous solution of methyl blue 35 c.c. 



1 per cent, aqueous solution of bluish watery eosin 45 c.c. 

 Distilled water 100 c.c. 



1. Mordant the sections in water, leaving them till all alcohol has 

 been replaced (five to thirty minutes). 



2. Stain in the above mixture, five to ten minutes. 



3. Wash well and differentiate in water; the effect may be varied 

 by the duration of the washing (ten to forty minutes). 



4. Dehydrate in alcohol, clear, and mount. 



When a sharper nuclear dye is desired the stain may be used as a 

 counter-stain after hematein. In this case the methyl blue solution 

 should be allowed to act only three to five minutes. The methyl blue 

 used in this method is a cytoplasmic dye and should not be confounded 

 with methylene blue. This is a valuable stain for differentiating cyto- 

 plasmic granules. 



Triacid Stain (Ehrlich) : 



Saturated aqueous solution of orange G 13 c.c. 



Saturated aqueous solution of acid f uchsin .... 7 c.c. 



Distilled water 15 c.c. 



95 per cent, alcohol 15 c.c. 



Saturated aqueous solution of methyl green. . . . 12.5 c.c. 



95 per cent, alcohol 10 c.c. 



Glycerin 10 c.c. 



Be certain that the solutions of the dyes are saturated, and mix in 

 the order given. 



The following formula by Mayer may be substituted: 



Distilled water 45 c.c. 



Glycerin 10 c.c. 



95 per cent, alcohol 25 c.c. 



Acid fuchsin 3 grm. 



