Cecil the seasick sea serpent swept to a Scituate shore Sunday and successfully stank up the surrounding sand.

However, a species classification yesterday by experts ruined the possibility of a lovable "sea monster" legend being passed down to future generations and at the same time deflated the value of thousands of "Cecil blubber" souvenirs taken from the creature Sunday at its dry-dock home on a Scituate beach.

Late Sunday night and into the early morning hours yesterday thousands of curiosity-seekers descended on Mannhill Beach, near Scituate, to view the carcass of a reported 30-foot, four-ton sea monster that had been washed ashore by Saturday evening's 11-foot mammoth high tide.

However, experts including Tyson Royal Roberts, Harvard's Assistant Curator of Fishes, dispelled all belief that the object at Mannhill was a sea monster.

They have definitely determined that the carcass is that of a mangled basking shark, which may have died at sea and was partially eaten by other sea life as it drifted ashore.

"When I saw that it was a cartilaginous skeleton, pieced such that parts could be missing and saw the fin configurations, I thought-large shark," said Paul Sieswerda, a salt water aquarist at the New England Aquarium.

Donald De Hart, Executive Director of the aquarium, and Sieswerda were both watching television when the news of the discovery was released.

"When I first saw it on TV it gave every indication of being a classical sea monster or at least something that didn't belong there," confessed Sieswerda.

De Hart sent Sieswerda to the Scituate scene to investigate the reports and try to preserve a part of the carcass for study. When he arrived there were about 250 college-age youths chanting and screaming.

After a quick view of the remains, the police approached the aquarist and asked him if he would take it away. Sieswerda later said, "I told them, 'I got a '53 Buick and I just couldn't get too much of it in,' so I figured I'd take the head 'cause it looked to be the most interesting."

When the head was cut off the crowd erupted with a cheer and then proceeded to cut off bits and pieces of the creature to take home.

Basking sharks have been reported in various books as having been mistaken for sea serpents on several occasions. The basking shark gets its name from its habit of staying on the surface of the water and lounging in the sun.

Unfortunately, this maneuver exposes the fish to the possibility of being hit and killed by passing ships. The shark, after rotting or being eaten as it washes in, may then be mistaken for a sea serpent. This may have been the case with Cecil, the once celebrated sea monster whose remains at last word were being unceremoniously fed to the New England Aquarium's garbage disposal.