150 HMMATEIN (HMMATOXYLIN) STAINS. 



This should be a 2J per cent, solution of ferric alum, not weaker. 

 Leave the sections therein (fixed to slides by the water method, 

 186) for six to twelve hours, or at least not less than three. Keep 

 the slides upright in the mordant, not lying flat. Wash out well 

 with water before staining. Stain in a " ripened " hsematoxylin 

 solution, i.e. one that has stood for four weeks [of course, if you 

 make it up with the ripened brown alcoholic solution recommended 

 237 sub. fin., this will be superfluous]. Stain from twenty-four to 

 thirty-six hours. Use the same staining solution over and over again 

 until it becomes spoilt ; for the solution after having been used 

 gives a more energetic stain, owing to its containing a trace of iron 

 brought over by the sections. Differentiate in a 2|- per cent, solu- 

 tion of ferric alum. Rinse for ten minutes in running water, clear 

 with xylol, not with any essential oil, and mount in xylol-balsam. 

 See also under " Centrosomes," and " Chromosomes," etc. 



BIELASZEWICS (Bull. Acad. Cracovie, 1909, 2 serie, p. 152) differentiates 

 with very weak solution of calcium chloride ; GTUARNIERI (Mon. Zool. 

 Ital., xvii, 1906, p. 44) with saturated solution of picric acid. 



GURWITSCH (Zeit. wiss. Mik., xviii, 1902, p. 291) floods sections on 

 the slide with mordant, warms on a water-bath till bubbles are given off 

 or the mordant becomes turbid, then stains with the hsematoxylin in 

 the same way. The whole process takes about ten minutes. 



HELD (Arch. Anat. Phys., Anat. Abth., 1897, p. 277) adds to the 

 staining bath a very little of the iron-alum solution until a scarcely 

 perceptible precipitate is produced. A dangerous practice. I find it is 

 not even safe to add a little of an over-used bath (supra). 



FRANCOTTE (Arch. Zool. Exper., vi, 1898, p. 200) mordants with tartrate 

 of iron, MALLORY (Journ. Exper. Med., v. 1900, p. 15) with chloride. 



243. Iron Haematoxylin (BUTSCHLI, Unters. uber mikroskopisehe 

 Schaume u. das Protoplasma, etc., 1892, p. 80). Sections treated with a 

 weak brown aqueous solution of ferric acetate, washed with water, and 

 stained in 0-5 per cent, aqueous solution of hsematoxylm. A stain of 

 extraordinary intensity, used by Biitschli for sections, 1 ^ in thickness, 

 of Protozoa. 



244. Weigert's Iron Hsematoxylin Mixture (Zeit. wiss. Mik., xxi, 

 1904, p. 1). Mix 1 part of a 1 per cent, solution of haematoxylin in 

 alcohol of 96 per cent, with 1 of a solution containing 4 c.c. of liq. ferri 

 sesquichlor., 1 c.c. of officinal hydrochloric acid (sp. gr. 1-124) and 95 

 of water. The mixture may be kept for some days (until it begins to 

 smell of ether), but is best used fresh. Stain sections for a few minutes ; 

 no differentiation is necessary. 



For an earlier process of WEIGERT'S (Allg. Zeit. Psychiatr., 1894, 

 p. 245) see last edition. 



MOREL and BASSAL (Journ. Anat. Phys., xlv, 1909, p. 632) stain in 

 bulk in Weigert's mixture with the addition of 1 c.c. of 4 per cent. 

 solution of acetate of copper. 



