SECTION TWO 



2. Immerse sections, which have been brought down to distilled 

 water as usual, for one half to one hour in iron haematoxylin 

 (Heidenhain) No. i. 



3. Rinse well in distilled water. 



4. Stain in iron haematoxylin (Heidenhain) No. 2 for a length of 

 time equal to the duration of stage 2 (above) ; then rinse thoroughly 

 in distilled water. 



5. Differentiate in solution C until only the nuclei are stained; 

 then wash well in water ; and stain in solution D for five minutes : 

 wash in distilled water. 



6. Stain one to five minutes in a mixture consisting of one part 

 of Solution E (above) and nine parts of distilled water ; then rinse 

 thoroughly in tap water. 



7. Differentiate in 1% phosphomolybdic acid for five to fifteen 

 minutes until collagen fibres are almost colourless; then, without 

 rinsing : 



8. Stain in the Fast Green FCF solution for half to two min- 

 utes. 



9. Differentiate by washing in water. 



10. Dehydrate in the usual manner; clear and mount. 

 Results: 



Nuclei are stained mauve to black; cytoplasm, varying shades 

 of red and mauve ; muscle, red ; collagen fibres and mucus, green. 



HAEMATOXYLIN - PONCEAU S - PICRO ANILINE 



BLUE 



For differential staining of connective tissue and muscle 



Solutions required: 



A. Haematoxylin (Weigert) A. 



B. Haematoxylin (Weigert) B. 



C. Ponceau, S 0-2% aqueous . . 100 ml. 

 Glacial acetic acid . . . . i ml. 



D. Picric acid, saturated aqueous . . 100 ml. 

 Aniline blue, water soluble . . o-i gm. 



E. Acetic acid 1% aqueous. 



125 



