1 The pharmacological potencies of the resins from three different samples of Brazilian marihuana (A, B and C) were determined through corneal areflexia in rabbits, decrease of spontaneous motor activity and induction of catatonia in mice, and decrease of rope climbing performance of rats.2 The Delta(9)-tetrahydrocannabinol (Delta(9) THC) content of the marihuanas, measured by gas...