Like a mermaid's jewelry box, this museum is dedicated to shells, yet it's much more than a covetous display of treasures. It's a crisply presented natural history of the sea, detailing the life and times of the bivalves, mollusks and other creatures who reside inside their calcium homes. It also shows the role of these animals and shells in human culture, medicine and cuisine. Fascinating videos show living creatures. It's nearly a must after a day spent combing the beaches.