PS: What a pity that Appel's annotations to "Lolita" are not followed by an Index ( no irony intended). I wanted to check the psychiatrist he quoted while mentioning fountainism and undinism since the only name that came to my mind was Kraft-Ebbing (Psycopathia Sexualis) and I know this is incorrect. Anyway, I think that the best way to proceed to understand "lunacy" in Nabokov's works would be to check, like SB did, psychiatric journals. I would also add standard texts like ...( now I remembered it) Havelock Ellis' and VN's collection of newspaper clippings on the subject of madness and perversion.

Wikipedia informs: "According to Ellis in My Life, his friends were much amused at his being considered an expert on sex considering the fact that he suffered from impotence until the age of 60, when he discovered that was able to become aroused by the sight of a woman urinating. His Sexual Inversion, the first English medical text book on homosexuality, co-authored with John Addington Symonds, described the sexual relations of homosexual men, something that Ellis did not consider to be a disease, immoral, or a crime; a bookseller was prosecuted in 1897 for stocking it. Other psychologically important concepts developed by Ellis include autoerotism and narcissism, both of which were later taken on by Sigmund Freud."

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