322 Microorgainsms (chap. 20) 



Sulfurous rinse: 



sodium metabisulfite, 10% (10 gm./lOO ml. wa- 

 ter) 6.0 ml. 



N hydrochloric acid (page 408) 5.0 ml. 



distilled water 100.0 ml. 



Aldehyde-fuchsin, see pages 168 and 287. 

 Metanil yellow: 



metanil yellow 0.25 gm. 



distilled water 100.0 ml. 



glacial acetic acid 2 drops 



procedure: 



1. Deparaffinize and hydrate slides to water; remove HgC^. 



2. Oxidize in chromic acid: 1 hour. 



3. Wash in running water: 5 minutes. 



4. Place in Schiff's reagent: 15 minutes. 



5. Rinse in sulfurous acid, .S changes: 1.5 mintites each. 



6. Wash in running water: 15 minutes. 



7. Stain in aldehyde-fuchsin: 15-30 minutes. 



8. Rinse off excess stain in 95% alcohol. 



9. Rinse in water. 



10. Counterstain lightly in metanil yellow: 1 minute. 



1 1. Rinse in water. 



12. Dehydrate, clear, and mount. 



results: 



mycelia — deep blue 



conidia — deep rose to purple 



background — yellow 



elastic tissue, mucin — deep blue 



Gomori's Methenamine Silver Nitrate Method (grocott's 

 ADAPTATION, 1955; mowry's modification, 1959) 



fixation: 10% formalin or any good general fixative. 



solutions: 



Methenamine silver nitrate. Stock solution: 



silver nitrate, 5% (5 gm./lOO ml. water) 5.0 ml. 



methenamine, 3% (3 gm./lOO ml. water) 100.0 ml. 



Working solution: 



borax, h% (5 gm./lOO ml. water) 2.0 ml. 



distilled water 25.0 ml. 



methenamine silver nitrate stock solution 25.0 ml. 



