XV] ANAEROBIC BACILLI 371 



cold water in order to set the top layers of the gelatine 

 quickly ; after this the tube is sealed with gutta-percha 

 paper and placed in the incubator. The result will be 

 apparent in twenty-four to forty-eight hours by the appearance 

 of a linear growth in the deep parts, which, as time proceeds, 

 tnlarges and shows all the differential characters of aspect, 

 progress, and liquefaction. 



Fiu. 148.— Stac Culture hf Hacillus E.\tekitidis Si'orogenes in ijeei' Sugar 

 Gelatine, inxubated for furtv-eight Hours at ^o C. 



Liquefaction has proceeded very rapidly; the liquefied gelatine is fairly translucent ; 



at the bottom is a fluffy tloccular mass, on the top is a gas bubble. 



Natural size. 



In Figures 147, 148, 149, and 150 four such stab cultures 

 in the depth of grape sugar gelatine are shown in which the 

 inoculation had been carried out by the capillary glass 

 pipette method, and from these will be seen the uniformity 

 of this method and the striking differences noticeable 

 between the four species here dealt with. In all four tubes 



B B 2 



