180 PLASMA STAINS WITH COAL-TAR DYES. 



Stain may be fixed in the tissues by means of sublimate, chromic 

 acid, bichromates, picric acid, or platinum chloride, followed by 

 molybdate of ammonium. 



It has also been found useful for staining, in hardened material, 

 the corpuscles of NISSL (q. v.) in nerve-cells. S. MAYER (Lotos, 

 Prague, 1896, No. 2) states that it also stains degenerating myelin. 

 The solutions that have been employed for staining fixed material 

 are strong aqueous ones, 1 per cent, to concentrated. 



309. Biebrich Scarlet (BRITISH DYES, Ltd., Huddersfield). A. K. 

 GORDON (British Medical Journ., 1917, p. 828) finds this an excellent 

 acid dye which never overstains and is not diffuse. Use in 1 per 

 cent, solution, or as recommended by SCOTT ( 676). 



I have used this stain a good deal and find it better than any other 

 plasm dye that I have tried. 



310. The Bosins, found in commerce under the names of Eosin, 

 Saffrosin, Primerose Soluble, Phloxin, Bengal Rose, Erythrosin, 

 Pyrosin B, Rose B, a PEau, etc., are all " acid " phthalein colours. 

 They are not quite identical in their properties. Most of them are 

 soluble both, in alcohol and in water, but some only in alcohol 

 (" Pritnerose a VAlcool "). 



They are all diffuse stains, formerly much used as contrast stains, 

 less so now. HANSEN (Anal. Hefte, xxvii, 1905, p. 620) adds 1 drop 

 of acetic acid of 2 per cent, to 9 c.c. of 1 per cent, eosin, which makes 

 the stain more selective. 



For Bengal Rose see GRIESBACH, Zool. Anz., 1883, p. 172. 



Eosin is a specific stain for red blood-corpuscles, and also for 

 certain granules of leucocytes (see under " Blood "). 



The yolk of some ova takes the stain strongly, so that it is useful 

 in some embryological researches. 



311. EHRLICH'S Indulin-Aurantia-Eosin, or Acidophilous Mixture, 

 or Mixture C, or Mixture for Eosinophilous Cells (from the formula 

 kindly sent me by Dr. GRUBLER). Indulin, aurantia, and eosin, of 

 each 2 parts ; glycerin, 30 parts. This gives a very thick, syrupy 

 solution. To use it, cover-glass preparations may be 'floated on to 

 it ; or sections on slides may have a few drops poured on to them, 

 the slide being laid flat till the stain has taken effect (twenty-four 

 hours for Flemming material). I find that with Flemming material 

 it gives a powerful and good stain, which is much more resistant to 

 alcohol than that of the EHRLICH-BIONDI mixture, and is, therefore, 

 much more adapted to ordinary work. The stain keeps well. 



ISRAEL (Prdktik. Path. Hist., Berlin, 1893, p. 68) gives a more 

 complicated receipt. 



