/(Studies on clostridium welchil type (A

1- In this thesis, trials were done for the prepara- tion of alpha toxin fron a laboratory stock smooth strain of £1. welchii type A, by using a simple medium ’which con- sisted of peptone (Difco), glucose, sodium chloride and disodium hydrogen phosphate.chloride concentration of O.~ and a disodium hydrogen phosphate concentration of 0.2% were the most favourable for maximal alpha toxin production from the Cl. welchii type A strain used. 3- The effect of varying hydrogen ion concentrations was experimente