MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



4. Wash well with tap water. 



5. Wash quickly in 70%, 90% and 95% or absolute alcohol. 



6. Mount directly in Michrome mountant or in Euparal. 



Result: 



Non-lignified cell walls, blue, Lignified cells, violet to red. 

 Bark cells, orange. 



Herbarium Specimens 



Solution required: 

 Solution D, as above. 

 Technique: 



1. Soak or boil the specimens in water. 



2. Cut sections and stain directly with solution D, which has 

 been well shaken immediately before use. 



Note: Prolonged treatment in the fixatives employed bleaches 

 the specimens sufficiently for the purpose of staining with chlorazol 

 azurine ; otherwise bleaching is not recommended. 



Reference: Armitage, F. D., ^. Roy. Micr. Soc.y 535, 826, i. 



/ am indebted to Mr. F. D. Armitage^ F.R.M.S.y of The Labora- 

 tory, Green End Road, Boxmoor, Herts, England, for information he 

 has given me regarding his use of this stain. 



CHLORAZOL BLACK 



A non-fading, general-purpose stain, which may be used 



for whole mounts as well as for sections. The stain requires 



no mordanting nor differentiation 



Nuclei and chromosomes are stained black, cytoplasm and 

 secreted products grey, by this stain, which has also been found 

 useful for infected plant tissues. 



Solution required: 



Chlorazol black, saturated in 70% 

 alcohol. 



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