The importance of plants to the existence and progress of man is beyond any doubt. Therefore, the ecological distruction, which progressively threatens our planet obliges us to concentrate our interest on the world of flora. Ancient civilizations took an interest in the flora both philosophical and scientific since in antiquity science had a philosophic substance and vice versa. Long before science had managed to interpret the miracle of growth and reproduction of plants, magic — a servant of religion — had assigned to the known species of vegetation supernatural properties. This continued to be an active practice among the believers until the Middle Ages and in some instances it still is. The healing power of a certain herb or plant has always created an immense impression on the mind of the ignorant, fanatic and superstitious man. Furthermore, his instinctive biases were reinforced by the hallucinatory properties of some special-herbs, which for this reason were deified and became an indispensible tool in every mystic ritual throughout the centuries.