124 THE AMERICAN MONTHLY [Apr 



alkaline raethylene-blue will keep a little longer, but they 

 require to be filtered occasionlly. 



ANILINE METHYL-VIOLET (EHRLICH-WEIGERT). 

 Saturated alcoholic solution of methyl-violet. . . .11 c c. 



Absolute alcohol 10 c c 



Aniline water 100c c. 



Making Aniline Water. — Aniline water is a saturated 

 aqueous solution of aniline oil. It is prepared by add- 

 ing 1 c. c. of aniline oil to 30 c. c. of distilled water and 

 shaking frequently for 30 minutes. It is convenient to 

 use a stoppered vial or large test tube for mixing it. Fil- 

 ter through a moistened filter paper. The filtrate should 

 be perfectly clear. If it is cloudy it should be refiltered 

 before using. 



Loffler's Method of Staining the Flagella of Bacteria. 



The staining methods employed to show bacteria in 

 sputum, etc., and of revealing spores in the bacteria do 

 not reveal the little infinitessimally small and delicate 

 wavey lines called flagella which fringe the organism in 

 many species and constitute its fins or wings and are used 

 to produce motion. The specimens easily loose these ap- 

 pendages and hence when it is proposed to demonstrate 

 them fresh and vigorous material must be found and be 

 handled with great care. Taking as small a quantity of 

 this material as is possible by soaking it apart in water 

 and lifting a droplet on a platinum wire loop, dry if on 

 a cover-glass using the heat gently for it could easily 

 burn off these little protruberances or whips from the bac- 

 terial body. This drying may be accomplished by hold- 

 ing the cover-glass specimen-side away from the heat, 

 and quickly passing it through the flame. If you do noT. 

 burn your fingers and thumb in which you hold the glas.** 

 y ou will not cremate the flagella. In 20 cc. water, dis- 

 olve 2 grams dry tannin, add 4 cc. ferrous sulphate so- 



