ActinomycesIsraeli, the agent of human actinomycosis and in particular of its cervico-facial form, is an endosaprophyte of the mouth becoming pathogenic following trauma to the buccal mucosa (for example sucking vegetable fibers) or common pyogenic infections. Demonstrative case histories show an excellent cure rate on high-dosage penicillin, associated, if need be, with treatment of the causal infection, surgical excision and radiotherapy. Prophylaxis consists of strict buccal hygiene with a view to eliminating infectious foci and active discouragement of grass sucking and its attendant risk of trauma to the buccal mucosa and penetration of the fungus.