STAIN TECHNIQUE 35 



207. Lanacyl Violet B is an acid dye, light 3 ; i gram in 95 

 ml. of distilled water, 1 ml. of 1 per cent sulfuric acid, and 5 ml. of 

 J per cent potassium dichromate. Parenchymatous tissue, cell 

 walls, and fungous mycelia are stained clear blue-violet very 

 similar in appearance to tissues taken from alum Haematoxylin. 



210. Lanacyl Blue BB is an acid dye. Cell walls and paren- 

 chymatous cells are stained light blue. The dye is not so good as 

 other blue acid dyes. 



211. Methyl Red is used principally as an indicator. It has 

 little value as a stain. 



Class IV. Disaso Colouring Matters 



248. Sudan III is unsuited for staining paraffin sections. 

 Blue-green algae are stained a fugitive orange-red in an alkaline 

 solution of the dye. As a fat stain this dye is used in the same 

 manner as Sudan IV, C. I. No. 258. 



252. Crocein Scarlet MOO, Carmoisine is an acid dye, light 

 3; J gram in 100 ml. of distilled water and 1 ml. of 1 per cent sul- 

 furic acid. On animal tissues this stain is more valuable than 

 Acid Fuchsine. Use Crocein Scarlet MOO for 10 minutes and 

 counterstain in Niagara Sky Blue, C. I. No. 520, for one minute. 

 With a mixture containing two parts Sun Yellow, C. I. No. 620, 

 and one part Crocein Scarlet MOO for 10 minutes, the counter- 

 stains are : ( 1 ) Niagara Sky Blue one minute for red, green, and 

 blue, (2) Aniline Blue, C. I. No. 707, which is not so selective as 

 Niagara Sky Blue, 15 seconds, or (3) Erie Violet BW, C. I. No. 

 387, five minutes for red, violet, and green. 



Sections of fungous tissues remain in Crocein Scarlet MOO 

 for 10 minutes and are counterstained in Niagara Sky Blue one 

 minute. Any of the combinations suggested for animal tissues 

 should be tried on fungi. On vascular plants this bright red dye 

 differentiates well with blue basic stains. It is similar to Azoru- 

 bine in color and staining reactions but is more fast. It counter- 

 stains well with (1) Aldehyde Green, C. I. No. 676a, one to ten 

 minutes, or (2) Opal Blue, C. I. No. 689, 30 minutes with a direct 

 transfer from the stain to 95 per cent alcohol. Fairly good con- 



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