Jefferson Airplane's fourth LP, "Crown of Creation" (released in September 1968), was a commercial success, peaking at No. 6 on the album chart. Grace Slick's "Lather", which opens the album, is said to be about her affair with drummer Spencer Dryden and his 30th birthday. "Triad", a David Crosby composition, had been rejected by The Byrds because they deemed its subject matter (a "ménage à trois") to be too "hot." Slick's searing sexual and social-commentary anthem "Greasy Heart" was released as a single in March 1968. A few tracks recorded for the LP were left off the album but later included as bonus tracks, including the Grace Slick/Frank Zappa collaboration "Would You Like A Snack?"