The conventioneers filled the hall. But no blue suits, no pinstripes, no oxfords were in sight.

Instead the Gaithersburg Holiday Inn lobby was transformed into a sea of rainbow-colored hair, orange and green polka-dotted baggy suits, red rubber noses, big, floppy tennis shoes and painted red smiles.

Five hundred clowns from all over the country descended upon Gaithersburg this week for the five-day 17th Annual Clowns of America National Convention to show off brightly colored costumes, discuss techniques, attend makeup workshops and, well, clown around. The convention runs through Sunday.

"We're all bozos," giggled Caroline Burkhart, whose clown name is Tickles.

"It's so much fun to be a clown," said Burkhart, 38, a Baltimore real estate agent in her other life, as she carefully drew a large red smile on her white-greasepainted face framed by a shock of bright yellow hair. "You can be really goofy and no one recognizes you."

Gaithersburg Mayor Bruce A. Goldensohn was on hand Wednesday night to welcome the unconventional conventioneers. "It was funny to watch patrons come in and quizzically ask, 'Honey, is this the right hotel?' " he said. "Actually, I feel a great kinship to everyone in this room. Most people say that the four city councilmen I meet with every week are a bunch of clowns."

But real clowning is serious business. Clowns have a strict code of ethics. "We can't drink or smoke when we're in makeup," said Burkhart as she dabbed circles of red greasepaint on her cheeks and tied her size 11 sneakers with green lace before the clowns' Cherry Blossom Princess Pageant.

About 50 clowns nervously lined up outside the hotel ballroom for the princess contest Wednesday night, waiting to strut on stage before four judges, including the mayor, and a standing-room-only crowd of clown lovers.

Miss Cherry Pits from Livonia, Mich., dressed as a huge red and white cherry pit stood in one corner anxiously awaiting her number to be called. One clown donned in zany pink-striped pants pulled at her white gloves and giggled. Miss Piggy from New York straightened her pig nose, which stood out among all of the red bulbous ones.

When the lights went down and the Greek music began blaring through the loudspeakers, the clowns approached the stage microphone one by one. "I'm 'Luv a Clown' from Florida," squeaked Nancy Peters, 49, from St. Petersburg, as she fluttered her two-inch eyelashes and pranced about in a clown suit dotted with red and white hearts.

One clown, dressed as a tree, complete with a foam rubber tree trunk on top of her head and standing in pots with green turf and rabbits over her feet, was too tall to fit on stage.

Donna (Bubblegum) Kerr, a petite jester all in pink from Omaha, was declared the winner amidst much applause and laughter, and she will ride in the Cherry Blossom Parade this weekend.

The clowns arrived from around the country. Pedro (Piruli) Santos, 33, of Puerto Rico, for example, founded the first clown organization in the Caribbean 12 years ago.

"I was destined to be a clown," said Santos in Spanish. "Two hours before I was born, my mother was watching the circus parade, went into labor and was rushed to the hospital. The doctor wrote on the back of my birth certificate, 'This boy will be a clown.' "