Possible Clues:

• Zeus turned into a swan to seduce her
• -- dog's life (toiled away)
• Title partner of 'the Swan' in a Yeats poem
• In Greek mythology, a queen of Sparta; small satellite of Jupiter
• The Gemini's mother
• Queen who fell for Zeus' swan song?
• Mythological subject of a Michelangelo painting
• Spartan queen admired by Zeus
• Mother of 41-Across