Possible Clues:

• Bishops' wear
• Bishops' hats
• Abbots' headgear
• Special hats making mister daft
• Headwear for British bishops
• Headgear for the Archbishop of Canterbury
• Toppers for archbishops of Canterbury
• Heads of church put on these unusual rites after mass
• Bishops' caps, in Britain
• Ornate hats for bishops