Related Clues:
- The silent Marx
- Chowder head?
- Half shell item
- Horn-honking Marx
- What Elvis did at the beach?
- What Elvis dug at the beach?
- Elvis "Do the ___"
- Proverbially reticent marine mollusc
- Mollusc with tightly-closed shell
- Tight-lipped one
- "On the half shell" bite
- Metaphor for reticence
- Pasta alle vongole ingredient
- Geoduck or quahog
- Blabbermouth's opposite