438 TEGUMENT ARY ORGANS 



with blotting paper, and treated with a mixture of 1 volume of 

 anilin to 2 volumes of xylol until sufficiently differentiated, when 

 they are brought into pure xylol. Very thin sections will require 

 more xylol in proportion to the anilin, viz. 1 : 3 or 1 : 4 ; thicker 

 ones may require more anilin, viz., 3:5 or 3:3. Gentian or 

 Krystallviolett will do instead of methyl violet, but not quite so 

 well. See also Ehrmann and Jadassohn, Arch. Dermatol, u. 

 Syphilis, 1892, 1, p. 303 ; ZeiL wiss. Mik., ix, 1893, p. 356 ; 

 Herxheimer, Arch. mik. Anat., liii, 1899, p. 510 ; and 

 RosENSTADT, ibid., Ixxv, 1910, p. 659 (takes the differentiating 

 mixture much weaker in anilin). 



Unna {Monatsschr. prakt. Derm., xix, 1894, p. 1 and pp. 277 

 et seq. ; Zeit. wiss. Mik., xii, 1, 1895, pp. 61, 63) has given a 

 whole series of methods, from which the following are some 

 extracts. 



1. Wasserblau-Orcein. Stain sections for ten minutes in 

 a neutral aqueous 1 per cent, solution of Wasserblau, rinse and 

 stain for five or ten minutes in a neutral alcoholic 1 per cent, 

 solution of Griibler's orcein. Dehydrate, clear, and mount in 

 balsam. This may be varied as follows : — 



(a) Ten minutes in the Wasserblau and thirty minutes or 



more in the orcein. 



(b) Take for the second stain an acid solution of orcein. 



(c) Stain for only one minute in the Wasserblau, but for thirty 



or more in the neutral orcein. 



2. Stain for half an hour or more in a strong solution of 

 haemalum, rinse, stain for half a minute in a saturated aqueous 

 solution of picric acid, and dehyrate for thirty seconds in alcohol 

 containing 0-5 per cent, of picric acid. 



3. Haemalum for two hours, neutral orcein as above for ten to 

 twenty minutes. 



More recently Unna advocates the process mentioned last 

 section. See also under Pasini's method, § 812. 



See also Ranvier, Arch. Anat. Mikr., iii, 1899, p. 1. 



931. Keratohyalin. The keratohyalin granules of the cells of 

 the stratum granulosum are soluble in mineral acids, and can be 

 digested in pepsin. They can be stained with picro-carmine, 

 alum ha^matoxylin, van Gieson's mixture, or Unna's Wasserblau- 

 orcein, last §. Fick {Centralb. allg. Path., xiii, 1902, p. 987 ; Zeit. 

 wiss. Mik., XX, 1903, p. 222) stains sections of alcohol material 

 for three to four minutes in concentrated aqueous solution of 

 Kresylechtviolett, differentiates in alcohol, clears in xylol, and 

 mounts in balsam. 



See also Unna, Monatsschr. prakt. Derm., xx, 1895, p. 69 ; the article 

 " Haut " in the Encycl. mik. Technik. ; and Unna and Golodetz, 

 Monatsschr. prakt. Derm., xlix, 1909, p. 95 ; Laffont, Bibl. Anat., 1909, 

 p. 209. 



