~Media for anaerobic cultures.~ In addition to the foregoing media, all of which can be, and are employed in the cultivation of anaerobic bacteria, certain special media containing readily oxidised substances are commonly used for this purpose. The principal of these are as follows: ~Bile Salt Broth (MacConkey).~-- 1. Weigh out Witté's peptone, 20 grammes (= 2 per cent.), and emulsify with 200 c.c. distilled water previously warmed to 60°C. 2. Weigh out sodium taurocholate (commercial), 5 grammes (= 0.5 per cent.), and glucose, 5 grammes (= 0.5 per cent.), and dissolve in the peptone emulsion. 3. Wash the peptone emulsion into a flask with 800 c.c. distilled water, and heat in the steamer at 100° C. for twenty minutes. 4. Filter through Swedish filter paper into a sterile flask. 5. Add sterile litmus solution sufficient to colour the medium to a deep purple, usually 13 per cent. required. 6. Fill, in quantities of 10 c.c., into tubes containing small gas tubes (_vide_ Fig. 104, page 161). Sterilise in the steamer at 100° C. for twenty minutes on each of three consecutive days. ~Glucose Formate Bouillon (Kitasato).~-- 1. Measure out nutrient bouillon, 1000 c.c. (_vide_ page 163, sections 1 to 6). 2. Weigh out glucose, 20 grammes (= 2 per cent.), sodium formate, 4 grammes (= 0.4 per cent.), and dissolve in the fluid. 3. Tube, and sterilise as for bouillon. ~Glucose Formate Gelatine (Kitasato).~-- 1. Prepare nutrient gelatine (_vide_ page 164, sections 1 to 7) and measure out 1000 c.c. 2. Weigh out glucose, 20 grammes (= 2 per cent.), and sodium formate, 4 grammes (= 0.4 per cent.), and dissolve in the hot gelatine. 3. Filter through papier Chardin. 4. Tube, and sterilise as for nutrient gelatine. ~Glucose Formate Agar (Kitasato).~-- 1. Prepare nutrient agar (_vide_ page 167, sections 1 to 8). Measure out 1000 c.c. 2. Weigh out glucose, 20 grammes (= 2 per cent.), sodium formate, 4 grammes (= 0.4 per cent.), and dissolve in the agar. 3. Tube, and sterilise as for nutrient agar. ~Sulphindigotate Bouillon (Weyl).~-- 1. Measure out nutrient bouillon (_vide_ page 163, sections 1 to 6 1000 c.c.). 2. Weigh out glucose, 20 grammes (= 2 per cent.), sodium sulphindigotate, 1 gramme (= 0.1 per cent.), and dissolve in the fluid. 3. Tube, and sterilise as for bouillon. ~Sulphindigotate Gelatine (Weyl).~-- 1. Prepare nutrient gelatine (_vide_ page 164, sections 1 to 7). Measure out 1000 c.c. 2. Weigh out glucose, 20 grammes (= 2 per cent.), and sodium sulphindigotate, 1 gramme (= 0.1 per cent.), and dissolve in the hot gelatine. 3. Filter through papier Chardin. 4. Tube, and sterilise as for nutrient gelatine. ~Sulphindigotate Agar.~--