All gelatin plates shall be incubated for 48 hours at 20 C. in a dark,
well-ventilated incubator in an atmosphere practically saturated with
moisture.[227]
All agar plates shall be incubated for 24 hours at 37° C. in a dark,
well-ventilated incubator in an atmosphere practically saturated with
moisture. Glass covered plates shall be inverted in the incubator. Any
deviation from the above described method shall be stated in making
reports.