Clyde Roper is one of those overeducated spoilsports who are taking the fear and mystery out of this world.

Roper is the giant squid man at the Smithsonian Institution. That is to say he is a marine biologist specializing in giant squids, those deep-sea monsters that some of us like to think are responsible for any number of unexplained marine disasters, including the continuing unpleasantness in the Bermuda Triangle.

Almost alone among those of his ilk, Roper has a giant squid to show off. It's lying in a huge vat of alcohol in the rotunda of the Museum of Natural History, and the only thing that's wrong with it, from his point of view, is that it's dead. Giant squids, he insists, are fascinating but not fearsome.

"It's a little beat up," he said, beaming as he bent over the display case. "It washed ashore on Plum Island [Massachusetts] in February 1980. The two long feeding tentacles were broken off, and the thin pink outer skin was mostly scoured away, but otherwise it's intact. She -- I'm assuming it's a she, because the big ones always have been so far -- weighed about 450 pounds in life, and probably was 28 to 30 feet long, which would make her a teenager, about half-grown. The largest one known was about 60 feet, and that's probably about as big as they get."

Roper is delighted with the beast and can't wait to dissect it. He will hold off until the end of the year, though, so the rest of us can see it.

But if while inspecting the squid you see a nice-looking fellow hanging around, slender and dark-bearded and of middling height and years, do not fall into conversation with him. That will be Clyde Roper, PhD, and he is full of facts you don't want to hear.

No, he will tell you, there are no megasquids lurking out there in the cruel sea, clutching ships with tentacles hundreds of feet long and devouring their crews, nevermore to see home, poor sailor lads.

"There just aren't any reliable reports," he will say, in his judicious scientific manner. "Some good observer, sometime, should have seen one; or part of one should have come ashore somewhere. Many estimates in the early literature were extrapolated from sucker scars on whales. They'd see huge scars on a mature blue whale -- they love giant squids, eat them all the time -- and calculate from that that the squid must have been 250 feet long or so. Well, baby whales eat squid too, and the scars grow as they do, so one that started out the size of a dime might get as big as a dinner plate."

Well, how about, say, a lone adventurer on the bleak ocean who lashes the tiller of his tiny craft and goes below to grab 40 winks, and a 60-foot squid slithers aboard, the 45-foot feeding tentacles snaking down through the hatch and winkling the victim out, nevermore to see home poor sailor lad?

"Afraid not," Roper says. "Squids just aren't aggressive, and anyway they probably mainly come to the surface when they're dead or dying. We don't really know, but I suspect they hang out around the edges of continental shelves, where there's plenty of fish and also rocks and canyons to hide in when the whales come around. We've got one good report of a large group of giant squids coming to the surface off the Grand Banks and acting pretty lively, but that's about it.

"It's doubtful that they even eat warmblooded creatures. Whales chase them, rather than the other way round -- squids may be having a population explosion these days, with the whales nearly wiped out -- and I wonder if a giant sauid could catch or overpower something like a seal. But we don't know much about their diet, because intact specimens like this one are very rare."

Here he cast a covetous eye on the pickled squid's suggestively rounded tummy. "I hope when we get in there we'll find she'd recently eaten. It would be wonderful."

Well, if giant squids don't eat us, how about we eat them? That's a lot of sushi, right?

"I'm afraid not," Roper said. "I had some once, at a party for a student who'd passed his doctoral exams. It was extremely bitter. It turned out that their tissues are full of ammonia ions, which are lighter than seawater and help give them bouyancy."

Thanks a lot, Doc.