A friend e-mailed me a British news story about an alien-like creature with writhing tentacles that washed up on a beach in Wales.

The seething mass turned out to be goose (also called gooseneck) barnacles stuck to a log.

I didn't get why a bunch of goose barnacles would cause such a fuss until I saw the pictures. On a 6-foot-long piece of wood, big around as a telephone pole, wiggled thousands of huge goose barnacles, their snakelike stalks resembling Medusa. These, I thought, are not your average goose barnacles.

Or maybe they are. The world's oceans host several species of goose barnacles, some larger than those we see in Hawaii, and some smaller.

Besides differing in size, a few of these barnacles are picky, setting up housekeeping in only one place on one kind of animal. Goose barnacles also win the prize for having the most bizarre name source of all marine creatures.

Unlike the familiar acorn barnacles that look like little volcanoes, goose barnacles stand on rubbery stalks. The animal permanently cements one end of its stalk to whatever it calls home.

At the other end is a white, heart-shaped shell consisting of five pieces, edged in brown, that open to allow six pairs of brown feathery legs to emerge and scoop up passing food. When threatened the plates close up tight.

Medieval Europeans declared the white shell of this crustacean a goose egg, believing geese hatched from the bottom of ships and emerged from the water fully feathered and flying.

The idea was ludicrous but had a practical basis. At that time the Catholic Church banned eating meat on Fridays and during Lent, but fish and shellfish were permitted. If geese hatched in the ocean, these “;marine animals”; could then be consumed on meatless days.

Some people today eat the goose barnacles themselves. The rubbery stalks are a popular food in Spain and Portugal. Since they've been overharvested there, these countries import goose barnacles from Canada and Morocco.

I've never eaten these barnacles (I once ate Chile's giant barnacles and found them disgusting), but some people in the U.S. must. Last week the New York Times published a recipe called “;Boiled Gooseneck Barnacles with Aioli.”;

One goose barnacle species has stalks growing as long as 30 inches, a meal in itself. The largest ones we see on items washing onto Hawaii's beaches have stalks 3 or 4 inches long.

Some tiny goose barnacle species settle on lobster mouths, and others live in the gills of crabs. One attaches only to objects on the ocean floor, such as sea urchins, and another lives only on jellyfish bells. Some goose barnacles stick to the shells of acorn-type barnacles living on whale fins.

Unfortunately, the larger species often choose to settle on the hulls of ships and boats, even as the vessel moves through the water at speed. If left to grow on a hull, these creatures create a drag that can reduce a boat's speed by 30 percent.

Some people on that beach in Wales viewed the barnacle-covered log as a writhing, tentacled sea monster, but I much prefer the naturalist Louis Agassiz's (1807-1873) description of a barnacle. He called it “;nothing more than a shrimp-like animal standing on its head in a limestone house kicking food into its mouth.”;

Strange, yes, but certainly no monster.

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