Using the standard strains such as Sh. flexneri 2 a, St. aureus and St. albus that are stocked in our laboratory, the author studied the glucolysis of these bacteria in the course of culture in the medium containing KCN or NaN(3) and also compared the enzymatic behaviors of each kind of bacteria in resting state while being cultured in the medium loaded with KCN or NaN(3). The results are as follows: 1. Both Sh. flexneri 2 a and St. aureus grow well in the medium loaded with 10⁻³ M KCN or NaN(3), and in the medium loaded with 10⁻³ M KCN th growth of St. albus is somewhat impeded but this strain grows well in the medium loaded with 10⁻² M NaN(3). 2. When KCN or NaN(3) is added to the medium in the course of bacteria culture, the glycolysis tends to be anaerobic; and morever, by the addition of KCN the accumulation of lactic acid increases, while by the addition of NaN(3) the accumulation of acetic acid. 3. On comparing the catalase and peroxidase activities of bacteria cultured in the medium loaded with KCN or NaN(3), both Sh. flexneri 2 a and St. albus lose their catalase and peroxidase activities in the medium loaded with 10⁻⁴ M KCN or NaN(3); while St. aureus likewise does not show these enzymatic activities in the medium loaded with 10⁻⁴ M NaN(3), but this strain retains these enzymatic activities to a marked degree in the medium loaded with 10⁻² M KCN. 4. In these bacteria being cultured in the medium containing KCN the enzymatic activity of lactic acid production from glucose is great, while in these bacteria cultured in the medium containing NaN(3) the acetic acid production from glucose is great.