62 



GENERAL MICROBIOLOGY 



and set on a level surface to cool. When the medium has 

 solidified, place the flask with the medium-side up. 



4. Mark the center of the flask on the outside with a 



FIG. 21. Giant Colony of Mold in Roux Flask. (Orig.) 



wax pencil and inoculate with a bent platinum needle in 

 one spot only. 



Note. When making mold inoculations moisten the sterile needle 

 with sterile water or medium before touching the spores; this insures a 

 positive inoculation. 



5. Keep at room temperature medium-side up. 



6. Examine and measure the diameter of the giant 

 colony from day to day and describe the typical growth 



