SECTION THREE 



D. Solution C . . 

 Distilled water 

 Absolute alcohol 



E. Lacmoid 

 Absolute alcohol 

 Distilled water 

 Solution C . . 



F. Solution C . . 

 Distilled water 

 Absolute alcohol 



G. Absolute alcohol 

 Clove oil 

 Xylene 



20 ml. 

 55 ml. 

 25 ml. 



0-25 gm. 

 30 ml. 

 70 ml. 

 3 to 5 ml. 



20 ml. 

 30 ml. 

 50 ml. 



equal volumes of each 



Technique: 



1. Fix material in formalin-acetic-alcohol. 



2. Unembedded sections, 5 to 40/x in thickness may be em- 

 ployed. 



3. Sections are taken from distilled water and immersed in 1% 

 tannic acid for five to ten minutes. 



4. Transfer to 2% ferric chloride for about five mins. 



5. Wash in distilled water (three changes). 



6. Examine under the microscope while the preparation is still 

 wet : the colour of the walls should be medium to dark grey, and 

 it may be necessary to repeat the above staining process to attain 

 this result as some phloem tissues stain less readily than others. 



7. Wash in three changes of distilled water. 



8. Immerse in solution D for thirty minutes. 



9. Transfer directly to solution E and leave therein for twelve 

 to eighteen hours, or longer if desired, as it is impossible to over- 

 stain. 



10. Transfer to solution F from ten seconds to ten minutes 

 depending upon the time at which the lacmoid destains. 



1 1 . Wash in 80% alcohol. 



12. Immerse in 90% alcohol for two to three minutes. 



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