Last February, the head Scribbler and some compatriots were sitting on the beach in Hawai’i (at the Banzai Pipeline, to be specific). One of us noticed that scattered amid the large, corn-colored grains of sand were lots of tiny, shiny white discs. On closer inspection, they were glossy spirals about the size of a pencil eraser, with a satisfying heft and the sweet liquid clink of marbles when you rolled them in your hand. They were opercula, said the group’s paleoceanographer.
The operculum is the snail’s equivalent of a hobbit’s door – a neat, round entrance that can be shut up securely to protect the occupant from intrusions by the outside world. When sea snails die, the operculum drifts away, separate from the shell, someday to wind up dashed on a distant beach by a barreling 4 to 6 foot Pipeline bomb.
Ordinarily, I wouldn’t trouble you with such details – even though, as it turns out, operculums are an age-old ingredient in incense. But in absently reading about them this evening I ran across this beautiful website dedicated to “the humble operculum: a celebration of the diversity and beauty … of this neglected element of gastropod mollusca.” The page has fine photos (like the ones above) of more than 35 types of shells that switch to the corresponding operculum when you mouse over them. Good enough to win webmaster Nancy Smith a Web award from (no kidding) worldwideconchology.com