52 W. H. E M I G 



Aniline Blue is of greater importance on plant tissues than on 

 animals. After a 24-hour stain in a basic dye such as Rhodamine 

 6G, C. I. No. 752, Acridine Red, C. I. No. 740, or Safranine, C. I. 

 No. 841, the best blue counterstain is Aniline Blue for five min- 

 utes. 



710. Isamine Blue 6B is an acid dye, light 3 to 4. The color 

 and staining properties of the dye are similar to those of Aniline 

 Blue ; it is less fast. 



712. Acid Blue G, Brilliant Acid Blue V is an acid dye, light 5. 

 Parenchyma is stained a light blue-green that is lacking in defini- 

 tion of details and in fastness. 



714. Patent Blue A, Brilliant Acid Blue A is an acid dye, light 

 4. Parenchyma is stained blue-green but the details of structure 

 are not presented clearly. 



720. Eriochrome Azurol V is a mordant dye, light 4 to 3 ; J 

 gram in 90 ml. of distilled water, 5 ml. of J per cent potassium 

 dichromate, and 5 ml. of 5 per cent sodium sulfate. Cell walls of 

 parenchyma are stained a clear blue and the cytoplasm, violet ; the 

 nuclei remain unchanged. The color is similar to that obtained 

 with Niagara Sky Blue. 



724. Aurin is the free acid Rosolic Acid used as an indicator. 

 Coralline, the sodium salt of Rosolic Acid, is used for the manufac- 

 ture of turkey red lakes. 



729. Victoria Blue B is a basic dye, light 3 ; J gram in 95 ml. 

 of distilled water, 5 ml. of 5 per cent ammonium alum, and J ml. 

 of acetic acid. A clear blue is obtained in parenchyma or scleren- 

 chyma. Sometimes this stain gives better contrasts with red acid 

 dyes than New Methylene Blue, C. I. No. 927. As a counterstain 

 use Victoria Blue B after Acid Fuchsine, C. I. No. 692, Biebrich 

 Scarlet, C. I. No. 280, Crocein Scarlet MOO, C. I. No. 252, or 

 Orange II, C. I. No. 151. 



731. Night Blue is a basic dye, light 4. The beautiful blue- 

 violet obtained on plant tissues is not very fast to light. 



736. Acid Blue B is an acid dye, light 5. Tissues stained with 

 this dye are not clearly differentiated ; they are too light and very 

 fugitive. 



