These colours may assume all kinds of fantastic shapes; they are never still, but constantly in motion, sometimes in a circular or to-and-fro manner, but more generally there is a kind of pulsation somewhat similar to that in the cinematograph.[13] Both native visions and white observations testify abundantly to the phenomena of synaesthesis, or the perception of the data of one sense in terms of another. Rouhier figures a painting made by an experimenter in which the sound of a bell is seen as a surréaliste aggregate of flowing, pulsating lines; and a subject of Havelock Ellis had a “curious sensation of tasting colors.” Crichtly mentions a color-taste synaesthesia also.[14] All these phenomena are physiological constants, as indicated by comparison of native visions with white experimenters’ observations. After visual hallucinations far the commonest are auditory ones. The writer, with a number of other observers, has noted the preternatural resonance, hollowness, discreteness and far-away quality of one’s own voice; if vocal disfunction were involved one would expect a raising of pitch here, hence it is probably auditory. On this point Dixon bears critical evidence:[15] The whole effect of the sound of the piano was most curious and delightful, the whole air being filled with music, each note of which seemed to arrange itself around a medley of other notes which appeared to me to be surrounded by a halo of colour pulsating to the music. Nasal hyperaesthesia was also present, though less evident than either the visual or auditory phenomena. The more strictly physiological effects may be summed up as follows:[16] _Skin_: no local irritation on injection of pan-peyotl; one observer reports partial skin anaesthesia, but this does not affect cutaneous reflex-excitability, which is much increased. _Respiration_: moderate amounts in Rana esculens produce no effect, but in toxic doses respiration becomes quicker and shallower, death ultimately occurring from paralysis of the respiratory center. In man respiration is ordinarily not affected, but some observers report shallower and more rapid breathing with “occasional long-drawn and deep sighs, and a painful feeling of suffocation.” Still another observer states that “respiration slows immediately after injection but is not influenced in a durable manner.”[17]