476 BACTERIOLOGIC TECHNIC. 



Czaplewski and E. Friinkel recommend that instead of anilin water, 

 2.5% carbolic acid water be employed. This has the advantage that 

 the solution does not decompose so soon as anilin mixtures. 



5. Loffler's Methylene-blue. To 100 c.c. of water is added 1 c.c. 

 of \% solution of potassium hydroxid, and 30 c.c. of concentrated 

 alcoholic solution of methylene-blue. The staining property of the 

 dye is intensified by the addition of the alkali. 



6. Acetic acid methylene-blue, according to M. Neisser, for the 

 staining of granules : 



(a) 1.0 gin. of methylene-blue is dissolved in 20 c.c. of 90 % alcohol, 

 and to this is added 950 c.c. of distilled water and 50 c.c. of glacial 

 acetic acid. 



(6) 2.0 gm. of Bismarck brown are dissolved in 1 liter of boiling dis- 

 tilled water (filter!). 



7. Bismarck Brown. Prepared like No. 1 (stains tissues, but stains 

 bacteria poorly). 



8. Alum Carmin. In 100 c.c. of a 5% solution of alum 2 gm. of 

 carmine are placed. It is boiled for an hour and filtered. It stains 

 nuclei and tissues, but not bacteria. 



g. Eosin. For staining the tissues about the bacteria. Two gm. 

 of eosin are dissolved in 100 c.c. of distilled water. 



10. Safranin. Three gm. of safranin are dissolved in 100 c.c. of 

 hot distilled water. 



(B) Differentiating Agents. 



1. Distilled water. 



2. Absolute alcohol. 



3. lodin, iodid of potassium solution (Gram's solution): 



lodin. pur 1.0 gm. 



Potassii iodid 2.0 " 



Distilled water 300.0 " 



4. Sulphuric acid, 25%. 



5. Acetic acid, 3%. 



6. Acid alcohol : 



Alcohol (90$) 100 c.c. 



Distilled water 200 " 



Pure hydrochloric acid 20 drops. 



(C) Mordants for Staining Flagella. 



1. Loffler's mordant : 10 c.c alcoholic solution of fuchsin ; 50 c.c. 

 cold saturated solution of ferrosulphate ; 100 c.c. 20% solution of 

 tannic acid. 



2. Bunge's mordant : 25 c.c. of officinal solution of ferric chlorid, 

 diluted twenty times ; 75 c.c. of a saturated aqueous solution of tannic 

 acid. Just before using, enough of a 3% solution of hydrogen peroxid 

 is added to give a reddish-brown color, and it is then filtered. (We 

 have always dispensed with this last addition. ) 



