I commend to the attention of this company _The Stuffed Owl: An Anthology of Bad Verse_ (D. B. Wyndham Lewis & Charles Lee, Eds.; Coward-McCann, 1930; Capricorn, 1962). Neither McGonagall nor the Sweet Singer of Michigan is there, however; the collection is confined to arguably reputable poets in their off moments. See also the section "Self-Parodies: Unconscious" in _Parodies: An Anthology from Chaucer to Beerbohm -- and After" (Dwight Macdonald, Ed.; Faber & Faber, 1960).