ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 93 



(4) Staining- and Injecting-. 



Mordants in Staining 1 Technique. * — After alluding to tho great 

 advances made in dyeing by means of mordants, decolorising and other 

 reagents, G. Marpmann suggests that similar combinations might be em- 

 ployed in microscopical technique. For this purpose the chloramin 

 colours are recommended, such as chloramin yellow C.G., which is fast 

 to alkalis, acids, heat, and chlorine, and chloramin violet R, which is 

 fast to acids and alkalis. 



The relations of pigments to organic cell-substances arc deserving 

 of special analysis. The following reactions are those best known : — 

 Substances containing pectin, vegetable mucus, or gums stain red with 

 ruthenium oxychloride in ammoniacal solution Rn 2 (OH) 2 Cl 4 + 7NH.,. 

 Tho aqueous solution 7 ,oVcr ^ s kept in dark bottles. With this stain 

 plus acetic acid bacteria stain blue. 



Vegetable fibres. The specimen is boiled with naphthol solution 

 in alcohol -1-. One drop of the solution with 10 drops of water arc 

 mixed on the slide. After boiling, sulphuric acid is added. This gives 

 a violet hue if vegetable fibres be present, and a brownish-red with 

 animal fibres. 



Cell-nuclei. A mixture of • 5 carmin, 20 alcohol, and 2 hydrochloric- 

 acid, is heated, and then 25 chloral hydrate added. In this fluid nuclei 

 stain a deep red in 10 minutes. 



Mucin is stained a dark-brown in 1 p.c. Bismarck brown. 



Muscle-fibres stain yellow in saturated aqueous solution of orange G. 



Cell-substance stains reddish with orange G. 



Nerve-fibres become deep red in saturated aqueous solution of acid 

 fuchsin (fuchsin S). 



Chromatin. Preparations stained with safranin are treated with one 

 per thousand hydrochloric acid alcohol. Thioniu stains the chromatin 

 bodies of the nucleus in a similar way. 



Diabetes blood is decolorised by methyleu-blue solution. The 

 solution consists of 1 part methylen-blue, 6000 parts of water, and 2 parts 

 of 6 p.c. caustic potash. One part blood is mixed with 2 parts of water 

 and 50 parts of the solution, and the preparation heated for 3 minutes in 

 a water-bath. Normal blood remains blue, while diabetes blood turns 

 yellow. 



Wood (lignin). Sections are stained with phloroglucin and hydro- 

 chloric acid a rose colour ; with orcein, reddish-violet ; with carbazol, 

 violet; with resorcin, bluish-violet; with naphthalin, yellow; with 

 pyrogallic acid, bronze yellow ; with indol, dark-red. 



Differential Stain for Cell Structures, f— J. H. Schaffner uses the 

 following stain for differentiating cell-structures. Stain first for two or 

 three hours with anilin-safranin (equal parts of anilin oil, water, and 

 saturated alcoholic solution of safranin). Then stain with picro-nigrosin 

 solution (distilled water, 100 ccm. ; picric acid, 1 gr. ; nigrosin, 1 gr. ; 

 first dissolve the picric acid and then add the nigrosin). Dehydrate, and 

 mount in balsam. The cell-wall stains black ; the cytoplasm bluish ; 

 spindle-threads green ; chromatin network brick-red ; granules of the 

 cell-plate black. 



* Zeitschr. f. angew. Mikr., vi. (1H00) pp. 169-73. 

 t Journ. Applied Microscopy, iii. (] ( J00) p. 'M0. 



