SPECIAL MEDIA 129 



Mac Conkey' s bile-salt broth. 



Sodium taurocholate 0.5$ 



Peptone 2.0% 



Glucose o . 5$ 



are dissolved in beef -broth by boiling; then filter and add 

 litmus-solution. 



Parietti's solution 



Carbolic acid 5 c.c. 



Hydrochloric acid 4 c.c. 



Water 100 c.c. 



Eisner's medium. i pound of sliced potatoes is grated 

 with a liter of water, and the juice expressed. After filtering 

 for 24 hours, add i per cent, peptone, i per cent, potassium 

 iodid, and 10 per cent, gelatin. 



Glycerinated potato. Prepare potatoes in the ordinary 

 manner and soak in a 25 per cent, solution of glycerin. Use 

 a glycerin -solution in the bottom of the tube. 



Hay-infusion. 10 g. of chopped hay are macerated with 

 1000 c.c. of water in the water-bath for 3 hours. Filter and 

 sterilize in autoclav for 10 minutes at 120. 



Wine-must. Wine-must is diluted with four times its 

 weight of water. Dissolve 0.5 per cent, ammonium tartrate, 

 macerate in the water-bath for i hour, filter, and sterilize in 

 Arnold for 3 consecutive days. 



Winogradsky' s solution (for nitric organisms). 



Dissolve in water 1000 c.c. 



Potassium phosphate i . oo g. 



Magnesium sulphate o . 50 g. 



Calcium chlorid o . 01 g. 



Sodium chlorid 2 . oo g. 



Distribute 20 c.c. in flasks, and add to each flask a small 

 amount of magnesium carbonate. Sterilize in Arnold for 3 

 consecutive days; then add to each flask 2 c.c. of a sterile 

 2 per cent, solution of ammonium sulphate. 



