He's mildewstaned he's mouldystoned
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Jump to navigationJump to searchMildew Lisa (page 40), referring to Wagner's "Tristan und Isolde", the famous dying aria of which begins: "Mild und leise" (Mild and quiet).
"Stan" and "Stone" refers to Shaun (and to Joyce's brother Stanislaus), "stem" or "tree" to Shem. (And if you put Tree and Stone together, you get "Treestone" or "Tristan".)