Related Clues:

• Jaunty tune disconcerted mighty Thor
• A number depart in it on time
• Piece one claims to play in time?
• Gershwin wrote orchestral ''Variations'' on it
• Gershwin standard from "Girl Crazy"
• George Gershwin song, a Top 30 hit for The Happenings in 1967
• Jazz standard written by George and Ira 17 Across