70 ANILIN COLOURS GIVING INDIRECT NUCLEAR STAINS. 



Dahlia is also a useful nuclear stain for fresh tissues (v. EHELICH, Arch. 

 . mik. Anat., xiii, 1876, p. 263). For these the aqueous solution must be 

 acidulated with (7*5 percent.) acetic acid; or you may stain in a neutral 

 solution, and wash out with acidulated water. Dehydrate with alcohol and 

 mount in turpentine colophonium. It is also useful for staining intra vitam. 

 See above, 93. 



For the staining of Ehrlich's " plasma cells," see post, Part II. 



104. Victoria Blue (Victoriablau) . (LUSTGAKTEN, Med. Jarhb. 

 ~k. Ges. d. Aerzte zu Wien, 1886, pp. 285 91). Stain (speci- 

 mens strongly fixed in "Flemming" some hours, lightly 

 fixed specimens a few minutes) in saturated aqueous solution. 

 Wash out in pure alcohol (about one minute, more or less). 

 You may clear with clove oil, but you had perhaps better take 

 cedar or bergamot oil, as clove oil washes out the colour very 

 freely. 



A most brilliant and useful nuclear stain, and one that I 

 think should be particularly recommended to the beginner, as 

 it is particularly easy to work with. Chromatm and nucleoli 

 blue. Cytoplasm, if well washed out, colourless ; if less washed 

 out, green or greenish blue. The " spongioplasm " is very 

 finely brought out by this method. 



Victoria has a special affinity for elastic fibres. For this 

 object Lustgarten recommends an alcoholic solution of the 

 dye diluted with two to four parts of water. Fixation in 

 chrom- osmium, or at least in a chromic mixture, is, I believe, 

 a necessary condition to this reaction. And you must stain 

 for a long time. 



Victoria has also a special affinity for mucus- cells, from 

 which it is not washed out by alcohol. 



105. Anilin Green. Use precisely as directed for Victoria blue, supra. 

 An extremely delicate and absolutely precise nuclear stain, nucleoli being 

 peculiarly brilliantly stained by it. I am unfortunately unable to trace the 

 history of the colour used by me, which may be identical with the Solidgriin 

 of Flemming (Arch. f. miJe. Anat, xix, 1881, pp. 317 and 742). It is well to 

 be even more careful in the use of clove oil than in the case of Victoria blue. 

 This colour seems not so generally useful as Victoria, as it does not give so 

 bold a stain. 



Like Victoria, anilin green has also a special affinity for mucus-cells. 

 See the paragraphs on " mucus-cells" in Part II. 



106. Henneguy's Permanganate Method (Journ. de VAnat. et 

 de la PhysioL, xxvii, 1891, p. 397). This method is based on 

 the fact, discovered by HENNEGUY, that permanganate of 

 potassium is a mordant for many anilin dyes, and will 



