TEGUMENTARY ORGANS. 367 



656. Plasma-fibrils of Epithelium. KROMAYER'S process (Arch, 

 f. mik. Anat., xxxix, 1892, p. 141 ; Zeit. f. wiss. Mik., ix, 1, 

 1892, p. 84, and ix, 3, 1893, p. 355) is as follows : Sections 

 are stained for five minutes in a mixture of equal volumes 

 of anilin water (p. 203) and concentrated aqueous solution 

 of methyl violet 6 B. They are well washed in water and 

 treated with solution of iodine in iodide of potassium until 

 they become blue-black (one to thirty seconds). They are 

 again washed with water, dried with blotting-paper, and 

 treated with a mixture of 1 vol. of anilin to 2 vols. 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 Kry stall - 

 violett will do instead of methyl violet, but not quite so well. 

 For some variations see Dermatol. Zeit., iv, 1897, p. 335; 

 Zeit. f. wiss. Mik., xiv, 3, 1897, p. 396 ; further, EHRMANN 

 and JADASSOHN, Arch.f. Dermatol. u. Syphilis, 1892, 1, p. 303 ; 

 Zeit. f. iviss. Mik., ix, 1893, p. 356 ; HERXHEIMER u. MULLER, 

 Arch. f. Dermatol., xxxvi, 1896, p. 93; Zeit. f. wiss. Mik., 

 xiv, 2, 1897, p. 216 (they used Weigert's Neuroglia stain) ; 

 SCHUTZ, ibid., pp. Ill, 218; and HERXHEIMER, Arch. mik. 

 Anat., liii, 1899, p. 510. 



For the same object UNNA (Monatssch. f. prakt. Dermatol., 

 xix, 1894, p. 1 and p. 277, et seq. ; Zeit.f. wiss. Mik., xii, 1, 

 1895, pp. 61, 63) has given a whole series of minutely 

 detailed methods, from which the following are some ex- 

 tracts. 



1. WASSERBLAD-ORCEIN. Stain sections for ten minutes 

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

 with water 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 method 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 with water, stain for half a minute in a 



