64 SPIROCIOETES. 



glycerine. The mixture is wanned and, if no precipi- 

 tate occurs, is poured on to the specimen and left for 

 two or three minutes. 



Schmorl uses Giemsa's stain for sections of tissue, 

 following it by a watery solution of alum. He admits 

 that this method is inferior to Levaditi's silver method. 



Forest stains first with Ziehl's carbol-fuchsine in the 

 cold, which dyes all spirochaetes except Sp. pallida, and 

 then stains with Giemsa's stain for twelve to sixteen 

 hours in the cold and for one-half hour at 70 C. 



Foix and Mallein note that the staining by Giemsa's 

 solution may be hastened by the use of an electric 

 current. 



Other Methods. Davidsohn recommends the use of 

 cresyl violet for staining Sp. pallida; Oppenheimer 

 and Sachs use carbolic gentian violet (concentrated 

 alcoholic gentian- violet solution, 10 c.c., 5 per cent, 

 solution of phenol, 100 c.c.). Proca and Vasilescu use 

 Gino de Rossi's cilia-stain (dissolve 50 grm. pure phenol 

 and 40 gr. tannin in 100 c.c. water and add to this 2.5 

 grm. basic fuchsine dissolved in 100 c.c. absolute alcohol. 

 Stain in this for ten minutes, wash and dry. Then 

 stain with a mixture containing concentrated alco- 

 holic gentian violet 10 c.c., phenol 5 grm., distilled 

 water 100 c.c.). 



Reitmann advises that films should be first treated 

 with 5 per cent, solution of phosphoric acid in water 

 for five minutes and then stained with carbol-fuchsine, 

 warmed. 



Goldhorn uses a complicated preparation of poly- 

 chrome methylene blue (methylene blue, lithium car- 

 bonate and eosin), and McNeal also uses methylene 

 blue and eosin (crude methylene blue 20 parts, pure 

 medicinal methylene blue 10 parts, eosin (yellowish) 

 20 parts, and pure methyl alcohol 100 parts. Stain on 



