STAIN TECHNIQUE 47 



658. Setoglaucine O is a basic dye, light 5. The dye is lighter 

 and less fast than Malachite Green, C. I. No. 657. It is used in 

 certain bacteriological media. 



662. Brilliant Green, Ethyl Green is a basic dye, light 5. 

 This dye has the same staining properties as Setoglaucine O, C. I. 

 No. 658. It, too, is used in bacteriological media. 



665. Alkali Green is an acid dye, light 5. The pale dull green 

 obtained with Alkali Green is one of the most fugitive. 



670. Light Green SF, Acid Green G, Fast Green FCF is an 

 acid dye; light 5 ; J gram in 100 ml. of distilled water and 1 ml. of 

 1 per cent sulfuric acid. Plant tissues are stained a fugitive green 

 or light blue-green. Fast Green FCF, which is the darker, should 

 be used only on thick sections of vascular tissues. Mature plant 

 materials taken from one of the basic dyes, Rhodamine, C. I. No. 

 752, Basic Fuchsine, C. I. No. 677, or Safranine, C. I. No. 841, are 

 counterstained in Fast Green FCF for 12 to 15 minutes. More 

 useful green cytoplasmic stains that have been described are the 

 combinations of Sun Yellow, C. I. No. 620, with New Methylene 

 Blue, Aniline Blue, or Niagara Sky Blue. On invertebrates and 

 whole mounts of fungi or algae, Naphthol Green B, C. I. No. 5, 

 applied with the aid of ferric alum produces a green more fast and 

 better differentiated than Fast Green FCF. Naphthol Green B is 

 also the better contrast green after iron Haematoxylin. 



A quadruple stain which includes Fast Green FCF may be 

 applied to vascular tissues. The first stain consisting of a mixture 

 of five parts Orange II and one part Fast Green FCF is used for 

 15 to 30 minutes. After a rinse in distilled water, the material is 

 counterstained in three parts Safranine and one part Methyl Violet 

 for 15 to 30 seconds. If more of the green is wanted, use the first 

 mixed stain longer than 30 minutes ; with a longer interval in Safra- 

 nine and Methyl Violet, the percentage of violet is increased. 



676. Pararosaniline is a basic dye, light 2 ; 1/10 gram in either 

 95 ml. of distilled water or 95 ml. of 50 per cent alcohol, 5 ml. of 5 

 per cent ammonium alum, and J ml. of acetic acid. The fuchsia on 

 plant tissues is brighter than the bluish red obtained with Basic 

 Fuchsine, C. I. No. 677. The dye may be used in staining bacteria 

 or in formulae calling for Basic Fuchsine. 



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