Technique: 



1. Paraffin sections are fixed to slides, and taken down through 

 the usual stages to 70% alcohol. 



2. Stain for four to forty-eight hours in the safranin (Solution 

 A). 



Note: The staining time depends upon the material. Angio- 

 sperm and Pteridophyte stems, leaves and roots, usually require at 

 least twenty-four hours. Weakly lignified or overchromated tissues 

 may need forty-eight hours. Gymnosperm materials need any- 

 thing from four to forty-eight hours. Ovaries and embryos require 

 four hours. 



3. Rinse thoroughly in water. 



4. Stain for five minutes in the crystal violet (Solution B). 



Note: This stain should be omitted on ovules, embryos and all 

 parasitic and saprophytic fungi ; in such cases proceed from stage 

 3 directly to stage 7. 



5. Rinse in running water for a few seconds. 



6. Rinse for a minute in Solution C. 



7. Stain for five minutes in the fast green - malachite green 

 (Solution D). 



8. Rinse briefly in running water. 



Note: The preparations will appear to be excessively over- 

 stained, but this does not matter. 



9. Rinse in Solution C to which 1% acetic acid has been added. 



10. Stain for five minutes in the orange 2 (Solution E). 



1 1 . Rinse in Solution F for a minute. 



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