Elaslin Tissue Staiyiing 167 



should be sharp bhuk, nuclei brown. If destained too far, return 

 slides to \'erhoeff's lor another 5-10 minutes. 



5. Transfer to sodium thiosulfate, 5% aqueous: 1 minute. 



6. Wash in running water: 5-10 minutes. 



7. Coimtcrstain in picro-ponceau: 1 minute. 



8. Differentiate in 95% ethyl alcohol: few seconds in each of 2 

 changes. 



9. Dehydrate in absolute alcohol; clear and mount. 



results: 



elastic fibers — brilliant blue-black 

 nuclei — blue to brownish black 

 collagen — red 

 other tissue elements — yellow 



comments: 



If elastic fibers stain unevenly, or not at all, \'erhoeff's solution is too 

 old. 



Orcinol-New Fuchsin (fullmer and lillie, 1956) 



fixation: any general fixative. 



solution: 



new fuchsin, C.I. 42520 2.0 gm. 



orcinol 4.0 gm. 



distilled water 200.0 ml. 



Boil for 5 minutes; add: 



ferric chloride, FeCls, 29.1% aqueous 25.0 nil. 



Boil for 5 minutes. Cool, collect precipitate on filter paper and dis- 

 solve in 100 ml. of 95% ethyl alcohol. 



procedure: 



1. Deparaffinize and transfer slides into absolute alcohol. 



2. Stain in orcinol-new^ fuchsin, 37 °C, 15 minutes. 



3. Differentiate in 70% alcohol, 3 changes, 5 minutes each. 



4. Dehydrate, 95% and absolute alcohol, clear and mount. 



results: 



elastic fibers — deep violet 



collagen — unstained by orcinol-new fuchsin 



comments: 



Slides can be counterstained with hematoxylin, safranin, or picro- 

 ponceau; of the three, safranin offers best color contrast. 



