The Frog at Forty-five.(The Talk of the Town)(La Grenouille)(Restaurant review)

Walking past 3 East Fifty-second Street early on a Monday morning, a stranger in town might get the idea that La Grenouille is a high-end flower shop. All that is visible through the window is a vast tangle of blooms and buds, berries and fruits, and leafy branches the size of small trees: in spring, these include blossoming fruit branches, irises, tulips, and sweet peas; in autumn, hawthorn, chrysanthemums, late-blooming hydrangeas, and orange Japanese lanterns.

If the wandering stranger happened by at about 7 A.M., he would see La Grenouille's proprietor, Charles Masson, a trim, dark-haired man in jeans and a sweater, standing tensely inside the front door. He'd be watching for a delivery truck loaded with the booty that he had selected, stem by stem, two hours earlier in the wholesale flower district in the West Twenties. Masson spends more than a hundred thousand dollars a year there on the materials from which he creates a series of lavish floral displays that flatter his clientele.

"This is the most relaxing thing about working here," he said one recent Monday, preparing to start on the week's arrangements. "It's my favorite part of the week."

The tradition of filling La Grenouille with monumental, soaring bouquets was begun by Masson's father, also named Charles, who, with his wife, Gisele, opened the restaurant forty-five years ago this week. It is the only survivor of an august group that included Lutece, Le Pavillon, La Cote Basque, and La Caravelle--the last three having been offshoots of the seminal restaurant in the French pavilion of the 1939 New York World's Fair, where Masson pere began as a waiter under the eye of the legendary Henri Soule.

"My father was a born host and would do just about anything to please a customer," Masson said. "He had a passionate respect for nature and loved to garden and to match seasonal foods and flowers. He was a painter, too, as was his friend Bernard Lamotte, who used a studio upstairs in what is now the banquet room." Works by both artists, along with some by the present Charles Masson, now hang on the gold damask walls of La Grenouille's dining rooms.

"At first, I didn't want to work in the restaurant," Masson went on. "I went to Carnegie Mellon to study art. But when my father became ill and died, in 1975, I quit school and came back to help my mother run it. I was only nineteen and very shy around people, especially our ...