SECTION III 



RELATION OF MICROORGANISMS TO THE CARBON CYCLE 



Exercise i 

 Fermentation of Cellulose in Impure Cultures (Liquid) 



1. Fill six large test-tubes about half -full of Omelianski's 

 solution (m. 48). 



2. Add four strips of filter-paper to each tube. 



3. Treat as follows: 



(a) I and 2, uninoculated. 



(b) 3 and 4, stable manure. 



(c) 5 and 6, garden soiL 



4. Incubate at 28° C. 



5. Cover the solution in tubes i, 3, and 5 with J-inch 

 layer of parafi&n oil. 



6. Examine the cultures at regular intervals, taking note 

 of the changes in the filter-paper. 



7. When the filter-paper shows the first evidences of 

 disintegration, make transfers to new tubes of Omelianski's 

 medium. 



Exercise 2 



Fermentation of Cellulose in Impure Cultures (Soil) 



I. Place 200-gram portions of garden soil in three i -liter 

 Erlenmeyer flasks. 



75 



