MOLDS, YEASTS, TORULAE, AND BACTERIA 185 



3. Inoculate with the mold and test for sugar 

 formation by the Fehling test from day to day. 



EXERCISE 5. CULTIVATION OF MOLDS IN 

 SOLUTION 



1. Preparation of Raulin's solution (see p. 42). 



2. Place about 50 c.c. of the solution in three Erlen- 

 meyer flasks and sterilize in the autoclave. 



3. Inoculate the surface with molds from three 

 species of molds. 



4. Incubate at 37 C. 



5. After growth has appeared examine the molds 

 and make sketches. 



EXERCISE 6. A STUDY OF MOLDS FROM LABORATORY 

 CULTURES 



Study cultures of molds furnished in the same 

 manner as outlined in the first five exercises of this 

 section. 



SECTION 3 



A STUDY OF YEASTS 



NOTE. All yeast cultures are to be incubated at 25 C. unless 

 otherwise directed. 



EXERCISE I. STUDY OF YEASTS FROM THE AIR 



1. Expose two plates of wort agar to the air in 

 different places, or if the plates exposed in the previous 

 section have colonies of yeasts these may be used. 



2. Transfer three colonies, which appear to differ 

 from each other by microscopic examination, to tubes 

 of slant wort agar, and incubate. 



