STAINING, PRACTICAL AND THEORETICAL 



5. Seal the edges of the coverslips with soft paraffin wax (M.P. 

 38° C), or Laktoseal, and examine under the microscope. 



Results: 



With Solution C {Pinacyanol ojily) 



Mitochondria in still living and motile cells are stained deep 

 blue to violet. 



With Solution D 



Mitochondria stained as above; nuclei and other cell granules 

 are stained red. 



Reference: Hetherington, D. C. (1936). 



PICRO - NIGROSIN 

 For eleidin and keratin 



Solutions required: 



A. Picric acid, saturated, aqueous. 



B. Nigrosin i% aqueous. 



C. Terpineol . . . . . . . . i volume 



Origanum oil i volume 



Technique: 



1. Tissues should be fixed in io% formalin, and frozen sections 

 employed. 



2. Sections are stained for five minutes in the picric acid solu- 

 tion. 



3. Rinse in distilled water. 



4. Stain in the nigrosin solution for one minute. 



5. Wash in distilled water. 



6. Rinse in 95% alcohol. 



7. Clear in Solution C. 



8. Mount in balsam or in Cristalite or D.P.X. 



Results: 



Eleidin : blue-black. Keratin : bright yellow. 

 Reference: Buzzi (1898). 



380 



