23 



spread as a thin layer upon a disinfected slide and allowed 

 to dry or coagulated by heat. A previously heated needle 

 or scalpel is then dipped into the material containing the 

 bacteria septic mouse-blood, for example and drawn 

 lightly over the surface of the culture substance on the 

 slide, or a series of punctures are made with the point. 



Fig. 3. Anthrax bacilli, pure (isolation) culture on blood serum. X 140. 



Thus a number of shallow furrows may be -made, in 

 and on the edges of which the bacteria are deposited. 

 The slides so prepared are then transferred to the 

 incubator or placed under a bell jar ; or, if they are 

 to be long preserved, in a thoroughly disinfected vessel 

 closed with cotton. A disadvantage of this method, 



