Related Clues:

• Silent type
• Happy mollusk?
• Cherrystone, e.g.
• Chowder flavor
• Simoleon
• Reticent one
• One who's close-mouthed
• Soup or sandwich ingredient
• Marine mollusk
• Untalkative one
• Secretive sort
• Brother of Groucho
• Quahog, e.g.
• A Marx man
• Arthur Marx, familiarly