STAINING, PRACTICAL AND THEORETICAL 



Recipe: 



Potassium dichromate . . ■ . . 5 gm. 



Mercuric chloride . . . . . . 10 gm. 



Sodium sulphate crystals . . . . 2 gm. 



Neutral formalin (40% formaldehyde) 10 ml. 



Distilled water . . . . . . 200 ml. 



Technique: 



Fix for twelve to twenty-four hours. Wash in running water for 

 the same time. Transfer to 80% alcohol; dehydrate; clear and 

 embed. 



Remarks: 



Not recommended for bacteria, cytoplasm degeneration, 

 necrosis or regeneration. 



Hermann's Fluid 



Recommended for : 

 Cytological work. 



Recipe: 



Platinic chloride 10% . . . . 6 ml. 



Osmic acid 1% , . . . • • 32 ml. 



Glacial acetic acid .. .. .. 4 ml. 



Distilled water . . . . • • 38 ml. 



N.B. — The solution should be freshly prepared. 



Technique: 



Fix from twelve to sixteen hours, wash in running water for 

 three to six hours ; then treat as for Flemming fixed-material. 



Remarks: 



While this fixative mordants chromatin for staining with basic 

 stains, it inhibits staining with acid stains. Good plasma staining 

 is difficult if not impossible after this fixative. 



Kleinenberg's Fluid 



Recommended for : 



Embryos; marine organisms, arthropods, chitinous material. 



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