Not a hallucinogen? 

This article states some effects of LSD use such as: " an experience of radiant colors, objects and surfaces appearing to ripple or "breathe," colored patterns behind the eyes", and then states that LSD is not truly a hallucinogen. Webster defines hallucinogen as a substance which brings about hallucinations when ingested, and defines hallucination as "a perception of objects with no reality usually arising from disorder of the nervous system or in response to drugs (as LSD)" quoted exactly. So yeah, I really think that going as far to say LSD isn't really a hallucinogen is stretching the definition of the word, considering that colors behind the eyes and surfaces moving around are actually hallucinations. Someone should edit these claims out of the article