CULTIVATION OF ANAEROBIC BACTERIA 83 



bottom upward, and any aerobins present will develop first 

 on top, this method being one of isolation. 



From the anaerobic germ grown in the lower part a stab 

 culture is made into another tube containing three-quarters 

 gelatin, the material being obtained by breaking test-tube 

 with the culture. (See Fig. 26.) 



Hesse's Method. A stab-culture having been made with 



Fig. 28. Frankel's method of Fig. 29. Buchner's method of 

 making anaerobic cultures (McFar- making anaerobic cultures (Mc- 

 land). Farland). 



anaerobic germs, gelatin in a semisolid condition is poured 

 into the tube until it is full, thus displacing the air (Fig. 27). 

 Esmarch's Method. Having inoculated a tube, the gela- 

 tin is rolled out on the walls of the tube, a "roll culture," 

 and the rest of the interior is filled with gelatin, the tube 

 being held in ice-water. The colonies develop upon the sides 

 of the tube and can be examined microscopically. 



