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SOIL BACTERIOLOGY 



3. Select a large and firm nodule, cut off, and immerse 

 for three to five minutes in mercuric chlorid solution 

 (i : 500), and finally in alcohol. 



4. Remove alcohol by flaming and place the nodule on a 

 sterile surface (flamed slide). 



' Fig. 5. Bacillus radicicola from a root nodule of alfalfa; X 1200. 



5. Cut open with a sterile knife and take out some of the 

 inner contents. 



6. Inoculate this bacterial mass from the nodule into a 

 few drops of water in a Petri dish. 



7. Make two or more loop transfers from the first Petri 



