SECTION FOUR 



Results: 



Mitochondria are conspicuously stained intense black. 



HAEMATOXYLIN - SAFRANIN 



For differentiating nucleoli and other nuclear constituents 



in plant cells 



D. Picric acid 1% in 95% alcohol. 



Technique: 



1. Fix sections to slide and take down to distilled water. 



2. Mordant with solution A for two to three hours. 



3. Wash in running water for five minutes. 



4. Rinse in distilled water. 



5. Immerse in the haematoxylin for an equal length of time. 



6. Differentiate very carefully with solution A, controlling by 

 examination under the microscope while the preparations are still 

 wet. 



7. When the nucleoli have been almost completely decolorized 

 remove the Iron alum solution quickly by rinsing in water. 



8. Wash in running water for an hour or longer. 



9. Immerse in solution D for twelve to sixteen hours. 



10. Differentiate for a few seconds in Picro-alcohol (solution 

 D.) 



1 1 . Wash with two changes of absolute alcohol. 



303 



