Reports acute cannabic psychoses in 560 Moroccans observed in Rabat between 1958-1965. Semeiological analysis distinguished 2 types of cannabism: (1) acute cannabic intoxication, a euphoric inebriation or sudden oneiric episodes of short duration (2-36 hr.), and (2) acute cannabic psychosis, induced by massive excess, consisting of oneiro-amnesic states that develop in 1-4 wk. Manic, confusional, anxiety-depressive, and stuporous forms were observed in both types. Euphoria appeared much less frequently in the psychotic stage. The symptomatology in over 50% of the psychotic cases contained discordant elements which were confirmed by Rorschach test, as well as graphic and pictorial productions. No case of acute cannabic psychosis revealed evidence of schizophrenic mutation from the viewpoint of autistic structuralization and a specific developmental tendency. Chronic cannabic psychoses due to massive and prolonged intoxication, appeared to be confined to demential states in gradual evolution, and sometimes present an atypical symptomatology with pseudoparanoid aspects.