SECTION THREE 



SAFRANIN - FAST GREEN, FCF 



A non-fading stain, satisfactory for nearly every type of 



plant material except the algae 



Solutions required: 



B. Fast Green FCF: 



Fast Green FCF saturated in equal parts Cellosolve 

 and absolute alcohol added in sufficient quantity to 

 give a stain of the desired intensity when mixed with 

 a mixture consisting of one part absolute alcohol and 

 three parts clove oil. 



t 



Technique: 



1. Paraffin sections are brought down to 70% alcohol, or free- 

 hand sections up to 35% alcohol. 



2. Stain in Solution A for two to forty-eight hours (gymno- 

 sperm material needs the minimum period) ; then wash off excess 

 stain in running water for a minute or so. 



3. Differentiate and dehydrate simultaneously with 0-5% picric 

 acid in 95% alcohol. 



4. Immerse in 95% alcohol to which four or five drops of 

 ammonia have been added from a few seconds to two minutes, but 

 no longer. 



5. Dehydrate quickly with absolute alcohol. 



6. Counterstain with Solution B fdr ten to fifteen seconds. 



7. Wash off excess stain with clove oil then clear in a mixture 

 consisting of two parts of clove oil, one part absolute alcohol, 

 and one part xylol. 



8. Remove the clearing mixture by washing for a few seconds 

 each in three changes of xylol ; then mount in balsam. 



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