418 SOME OTHER HISTOLOGICAL METHODS. 



are available. In all of them Mastzellen are distinguishable from plasma 

 cells by the reddish coloration of their granules. 



793. Plasma Cells and Mastzellen. BEEGONZINI (Anat. Anz. t 

 vi, 1891, pp. 595600; Zeit. f. wiss. Mik., ix, I, 1892, p. 95) 

 gives the following : Mix 1 volume of 0*2 per cent, solu- 

 tion of Saurefuchsin with 2 volumes of a like solution of 

 methyl green, and 2 volumes of a like solution of gold- 

 orange, and filter through cotton wool. Stain alcohol or sub- 

 limate sections (after washing in water) for three to four 

 minutes, wash for one or two minutes in water, bring into 

 absolute alcohol for two minutes, clear in bergamot oil or 

 pure creosote, wash in turpentine, and mount in balsam. 



One sort of gold- orange precipitates methyl green, and there- 

 fore cannot be used in this mixture. Orange G may be used 

 instead (thus giving something very like Ehrlich-Biondi mix- 

 ture), but in this case the acidophilous granules will stain grey- 

 ish instead of red or orange. Basophilous granules ought to be 

 green, weakly acidophilous granules red, strongly acidophilous 

 ones orange or brown, nuclei always green. Other details 1. c 



794. Plasma Cells. JADASSOHN (Arch. f. Dermatol. u. Syphilis, 

 Erganzungsheft 1, 1892, p. 58 ; Zeit. /. wiss. Mik., ix, 2, 1892, p. 226) re- 

 commends staining for nottoo long in a 1 : 2000 strongly alkaline or borax 

 solution of Thionin, and washing out with acidulated water. Unfortunately 

 this colour is, I believe, no longer obtainable in commerce. 



795. Elastic Tissue. Two of the most salient characters of 

 elastic fibres are that they have a great affinity for osmium, 

 staining with much more rapidity than most other tissue- 

 elements, and that they are not changed by caustic soda or 

 potash. A further character is that they have a great affinity 

 for certain anilin dyes, especially Yictoria blue. 



For a review of the older methods of BALZEE, UNNA, LUST- 

 GARTEN, and HEEXHEIMEE, see the paper by MAETINOTTI in Zeit. 

 f. wiss. Mik., iv, 1, 1887, p. 31. 



LUSTGAETEN'S process, which is simple, and gives very good 

 results, has been given in 104. The colour used by him was 

 called " Yictoriablau 4 B," and this is probably an important 

 detail. 



But perhaps the best method is that of MAETINOTTI (1. c.). 

 Fix in a chromic liquid, wash, stain for forty-eight hours in 

 strong (5 per cent. Pfitzner's) solution of safranin, wash, 

 dehydrate, clear, and mount in balsam. Elastic fibres are 



