392 THE TYPHOID BACILLUS 



to 5 c.c. of ox bile previously sterilized in the autoclave. The mixture is 

 incubated at 37 C. for 12-24 hours and then plated out on malachite green 

 agar (p. 409) or better, litmus-lactose-agar. 



Kayser adopts a similar technique and sows 2*5 c.c. of fresh blood in 5 c.c. 

 of sterile ox bile and then plates on Conradi-Drigalski's medium (p. 407). 



2. Conradi's technique. Conradi uses ox bile containing 10 per cent, of peptone 

 and 10 per cent, of glycerine. The mixture is sterilized at 100 C. for 2 hours. A 

 small clot of the suspected blood is added to 5 c.c. of the sterilized medium and incu- 

 bated at 37 C. for about 15 hours. Plates of litmus-lactose-agar are then sown with 

 the cultures. 



3. Roosen-Runge's technique. Glycocholate of sodium is used instead of bile. 

 The medium is an ordinary agar medium to which 10 grams per litre of glycocholate 

 of sodium have been added. 



4. Dlinschmann's technique. Dlmschmann is of opinion that the valuable con- 

 stituent in bile is taurocholate and not glycocholate of sodium. He recommends 

 the following medium : 



Gelatin, - 5 grams. 



Agar, - 30 



Lactose, - 40 



Peptone, 10 



Taurocholate of sodium, - 20 ,, 



Water, - - - 1000 c.c. 



When only a small quantity of blood is available it is used for sowing surface 

 plates on bile-salt-agar. 



Detection in sputum. To detect the typhoid bacillus in sputum employ 

 one of the methods described in Chau. XXIII. 



