30 Hli^TOLOGICVL TECHXIC 



in distilled water, placed for five minutes in 50-per-cent. alcohol, then 

 in strong alcohol, cleared in xylol and mounted in xylol-balsam. 

 This stain works best after Zenker's fluid fixation. 



(7) Mallory's Phosphotungstic Acid H.^matoxylin Stain for 

 Connective Tissue. 



Haematoxylin (or ha^malein ammonium), o.i gm. 



Water, 80. c.c. 



Phosphotungstic acid (Merck), lo-per-cent. aqueous 



solution, 20. c.c. 



The haematoxylin should be dissolved in a little water with 

 the aid of heat and, when cool, added to the rest of the solution. 

 Allow to ripen for several weeks or months. Or, if it is de- 

 sired for immediate use, the solution can be ripened by the 

 addition of 10 c.c. of a 1/4-per-cent. solution of potassium per- 

 manganate. 



Tissues should be fixed in Zenker's fluid (p. 8). 



1. Treat sections with iodin solution to remove mercury precipi- 

 tate, 5 to 10 minutes (p. 10.) 



2. Several changes 95-per-cent. alcohol. 



3. Water. 



4. One-fourth-per-cent. aqueous solution potassium permangan- 

 ate, 5 to 10 minutes. 



5. Wash in water. 



6. Five-per-cent. aqueous solution oxalic acid, 5 to 10 minutes. 



7. Wash thoroughly in water. 



8. Phosphotungstic acid hfematoxylin solution, twelve to twenty- 

 four hours. 



9. Dip for a few seconds in 95-per-cent. alcohol. 



10. Clear in carbol-xylol and xylol and mount in xylol-damar. 

 (8) Mallory's Aniline Blue Stain for Connective Tis- 

 sue. — Tissues should be fixed in Zenker's fluid (p. 8). 



1. Stain thin sections in a o. 2-per-cent. aqueous solution of acid 

 fuchsin for five to ten minutes. (This step may be omitted.) 



2. Stain in the following solution for twenty minutes: 



Aniline blue (soluble in water), 0.5 gm. 

 Orange G., 2.0 gm. 

 Phosphomolybdic acid, i-per-cent. aqueous solu- 

 tion, 100. o c.c. 



3. Decolorize in several changes of 95-per-cent. alcohol. 



