His fourth case, felicitiously, requires Detective Mole to make just one simple deduction--the culprit that squirted Captain Bill Laughing Gull and made off with his precious black pearl, and attacked Morris Sea Turle the same way the next day, must be . . . well, ""who would be on a lonely beach when the tide was out""? It is, of course, a giant clam--who didn't mean any harm, it turns out: he just didn't like someone tramping over his head and disturbing his rest. Some corny jokes about laughing gulls laughing and clams clamming up add a few titters to the pint-sized puzzle.