SECTION THREE 



Technique: 



1 . Sections of fresh material are taken from distilled water and 

 immersed in Solution A (above) for one half to one hour. 



2. Wash well with several changes of distilled water. 



3. Stain the nuclei with alum carmine solution for a few min- 

 utes , then wash well with distilled water. 



4. Dehydrate through ascending grades of alcohol as usual, 

 clear in xylol ; mount in D.P.X. or Cristalite. 



Results: 



Nuclei, red. Iron (if present), blue. 



Lecithin 



Solutions required: 



A. Scarlet R (Botanical). 



B. Delafield haematoxylin. 



Technique: 



1. Fat is removed from sections by immersion overnight in 

 acetone, in a stoppered jar or well-corked tube. 



2. Fix sections to slides; rinse in two changes of pure 

 acetone. 



3. Stain the scarlet R solution for about ten to fifteen 

 minutes. 



4. Wash quickly with 70% alcohol. 



5. Wash in distilled water. 



6. Counterstain with Delafield haematoxylin for two to ten 

 minutes. 



7. Blue and wash in tap water. 



8. Mount in glycerine or Aquamount. 



Results: 



Lecithin (if present), red. Nuclei, blue. 



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