17C PLASMA STAINS 



water. He has also {Zeit. wiss. Mik., xi, 1894, p. 490) used a 

 similar mixture for nerve-cells. 



This is a famous stain. To get it right you must have the 

 proper specimens of stains. This applies more to eosin than to 

 the other stain. If the made-up stain is red, or blue, it is incorrect, 

 it should be neither of these colours, but a reddish-purple.* 



357. Violet B (or Methyl Violet B) (S. Mayer, Sitzh. k. k. Akad. wiss. 

 Wien, ill, Abth., Februarj^ 1882). Used in solutions of 1 grm. of the 

 colour to 300 grm. of 0-5 per cent, salt solution, and with fresh tissues 

 that have not been treated with any reagent whatever, this colour is said 

 to give a stain so selective of the elements of the vascular system that 

 favourable objects, such as serous membranes, appear as if injected. 

 The preparations do not keep well ; acetate of potash is the least unsatis- 

 factory medium for mounting them in, or a mixture of equal parts of 

 glycerin and saturated solution of picrate of ammonia (Anat. Anz., 

 1892, p. 221). See also under " Plasma-fibrils." 



The allied dye, Crystal Violet, has been employed for staining 

 sections, e.g. by Kromayer and others. 



According to Conn {op. cit.) synonyms are : Violet C, G, or 7B, 

 Hexamethyl violet, methyl violet lOB, gentian violet. Solubility of 

 Conn's specimen, at 26° C, in water 1-68 per cent., In alcohol 13-87 per 

 cent. 



Benda {Neurol. Centralb., xix, 1900, p. 792) stains in a mixture 

 of 1 vol. saturated sol. of the dye in 70 per cent, alcohol, 1 vol. 

 1 per cent. sol. of hydrochloric acid in 70 per cent, alcohol, and 2 

 vols, of anilin water, the liquid being warmed until vapour is given 

 off, then cooled and the sections dried with blotting-paper, treated 

 one minute with 30 per cent, acetic acid, dehydrated with alcohol 

 and cleared with xylol. Refer to § 697 for mitochondria and 

 granules. 



Kresyl Violet. An oxyazin dye, giving metachromatic stains. 

 Heuxheimer {Arch. mik. Anat., liii, 1899, p. 519, and liv, p. 289) stains 

 sections of skin with Kresyl-echtviolett. Nuclei blue, plasma reddish. 

 Similarly Fick {Centralb. allg. Path., xiii, 1902, p. 987 ; Zeit. wiss. Mik., 

 XX, 1903, p. 223), staining for three or four minutes in a concentrated 

 aqueous solution, and diiferentiating in alcohol until the connective 

 tissue has become colourless. Keratohyalin violet-red to salmon- 

 coloured. 



358. Benzoazurin may be made to give either a diffuse or a nuclear 

 stain, according to Martin (see Zeit. wiss. Mik., vi, 1889, p. 193), 



359. Rawitz " Inversion " Plasma Stains. It has been discovered 

 by Rawitz that by means of appropriate mordants certain basic anilins, 

 which by the usual methods of regressive staining are pure chromatin 

 stains, may be made to afford a pure plasma stain, thus giving an 

 " inversion " of the usual stain. The stain is a vile one. For details 

 see fourth edition, or Rawitz {Sitzb. Gesnaturf. Freunde, Berlin, 1894, 

 p, 174 ; Zeit. zviss. Mik., xi, 1895, p. 503 ; and his Leitfaden f. hist. 

 Untersuchungen, Jena, 1895, p. 76). 



360. Artificial Alizarin (Rawitz, Anat. Anz., xi, 10, 1895, p. 295). 



* For further information refer to § 1152. 



