SINCE the discovery of d4yser-gic acid diethylamide in 1943, a voluminous literature has accumulated concerning its effects on a variety of animals including man.1 Despite the mass of published reports, definitive evidence is generally lacking particularly with Iegard to the subjective and behavioral effects both during and subsequent to the LSD induced state. It well established that this powerful agent produces major alterations in cerebral processes and central autonomic functions. There is also ample evidence indicating a markedly lowered threshold for arousal (Key & Bradley, 1960) and an increased sensitivity to stimuli in all modalities (Klee, 1963). These psychopharmacological effects parallel the findings of clinical and behavioral studies at least on the molar descriptive level. Pronounced perceptual changes have been almost invariably demonstrated with concomitant alterations in affect, ideation, and the relationship between subject and environment (Hoffer, 1965). Beyond these rather global findings, results have been inconsistent and often contradictory even within -species far less complex than man (Cohen;.'