Outwardly, they could hardly seem more different. One is petite and deliberate, the other a bit plump and more spontaneous.

Where Nancy Reagan and Raisa Gorbachev are similar, though, is where it counts most. Both are said to be influential with their husbands. And both are unquestionably valuable assets to those husbands, first ladies whose own "summit" went remarkably well this week.

The comparisons -- and therefore ratings of their performances here -- have been inevitable. After months of speculation about their clothes, their influence, their style of doing things and their personalities, who would have thought that the wives of the world's number one capitalist and the world's number one communist would end up holding hands?

Yet it happened, if briefly, today at one of their three joint appearances, this one when they met Swiss First Lady Ursula Furgler to leave a common message of hope for "peace and harmony for all mankind" in the cornerstone of a new Red Cross museum.

If it couldn't exactly be taken as a sign of the Soviets and Americans kissing and making up politically, it did say something about how they got along here.

Tonight at the reciprocal dinner the Reagans gave the Gorbachevs, Nancy's and Raisa's laughter rang out loud and clear above the media's whirring, clicking cameras that were crowded into a tiny dining room at Maison de Saussure, the 18th-century villa where the Reagans have been staying this week.

Reagan and Gorbachev weren't answering questions about how their meetings went any more forthrightly at dinner than they had when the Gorbachevs arrived a few minutes earlier in their Russian Zil limousine. And Mrs. Reagan and Mrs. Gorbachev weren't talking either.

As they headed inside the villa, Mrs. Gorbachev called out "I don't know" in English when reporters asked if Reagan and Gorbachev had good news to toast during dinner.

"The news is so good," the president said, "we're going to hold it 'til tomorrow."

In the dining room, Gorbachev said: "Just wait a little. We'll tell you everything."

The Reagans served an elegant gourmet dinner for 12, with a menu that included souffle' of lobster, supreme of chicken perigourdine, endive salad, mousse de fromage with avocado and hot lemon souffle' with raspberry sauce. The wines were Californian -- a 1983 Silverado Chardonnay, a 1974 Stag's Leap Cabernet Sauvignon and a 1982 Iron Horse Blanc de Blanc.

The guests were served on cream and gold U.S mission china at a black walnut table laid with white place mats and decorated with white flowers in silver bowls. Silver Tiffany paperweights engraved with American and Soviet flags were given as souvenirs. Each was encased in blue leather bearing the presidential seal and inscribed with the words, "The meeting of President Ronald Reagan and General Secretary Mikhail Gorbachev, Geneva, November 1985."

Reagan sat between Mrs. Gorbachev and Soviet Foreign Minister Eduard Shevardnadze. Mrs. Reagan sat between Gorbachev and First Deputy Minister of Foreign Affairs Georgi Korneiko. Reagan and Gorbachev sat across from each other, with Anatoliy Dobrynin, Soviet ambassador to the United States, ending up at the head of the table.

The U.S. guests were Secretary of State George Shultz, White House chief of staff Donald Regan, national security affairs adviser Robert McFarlane and U.S. Ambassador to Moscow Arthur Hartman. Andrei Alexandrov-Agentov, Gorbachev's personal aide, was the other Soviet guest.

The dinner capped another full day of activities for both first ladies. Mrs. Reagan went to the U.S. mission; visited the College du Le'man, an international children's school; and taped messages for the United Nations' children's fund vaccination campaign. Mrs. Gorbachev visited the World Health Organization and a 105-acre Swiss dairy farm.

At the Red Cross ceremony early in the day, the two greeted each other warmly and exchanged their messages -- identical ones written in English and Russian -- before placing them in the time capsule with Mrs. Furgler's, which was written in French.

In the afternoon, at Mrs. Gorbachev's reciprocal tea for Mrs. Reagan, the two women talked for 50 minutes about their "busy lives with husbands and children," according to Elaine Crispen, Mrs. Reagan's press secretary.

Mrs. Gorbachev served a formal Russian tea, and Mrs. Reagan -- usually a light eater -- managed to put away some cabbage pie, berry pie and blini with caviar while sipping her tea and honey, Crispen said.

The two women had appeared anxious to get on with the tea when Mrs. Reagan arrived. "We don't have much time and we have things of substance to discuss," Mrs. Gorbachev told reporters in Russian.

When someone asked what those things were, Mrs. Gorbachev said: "I cannot tell you that now because it's up to Mrs. Reagan." Asked whether she and Mrs. Reagan could do anything together to promote world peace, she replied in Russian, "All we can do, we shall do."

Their portrayal of the teas as serious affairs came amid controversy over comments by Regan, who said in an interview before the summit that most women would not understand such issues as arms control, international conflicts and human rights violations, and would prefer to read about the "human interest" aspects of the summit, including such things as the first ladies' teas.

Mrs. Reagan told reporters she hadn't seen Regan's statement. But answering a general question on whether women concerned themselves with substantive issues, she replied: "I'm sure they do."

If Mrs. Gorbachev began her week a little wary of western journalists, she seemed to quickly get over it. Spunky at times, rising to the occasion at others, she revealed a mind of her own.

She seemed to be enjoying her exchanges with the press, and before long was even cutting them short the way an American celebrity might.

If she outscored Mrs. Reagan at all, it was at the Red Cross, where she delivered her short speech from memory with all the finesse of the university lecturer she is. Mrs. Reagan read hers, looking up from the text only two or three times.

And though Mrs. Gorbachev made valiant attempts several times to speak a little English, Mrs. Reagan made none at all in Russian.

But if Mrs. Gorbachev displayed pluck and spontaneity, Mrs. Reagan's self-assurance was equally impressive. Seemingly unconcerned about sharing the international spotlight with the Soviet first lady, she chalked up kudos for her own handling of the press at standup press conferences.

On the fashion front, however, there was no contest. Rather than continents apart, the two women were worlds apart on what they consider stylish.

Mrs. Gorbachev was well-groomed and attractive, but by western standards, not especially elegant or chic. Mrs. Reagan, known for high fashion, was as stylish as usual.

Mrs. Gorbachev appeared to be a bit overdressed at times, notably when she wore dangling diamond earrings and a dressy black suit for Mrs. Reagan's Tuesday afternoon tea. Tonight, though, she turned up at the Reagans holding her own in a dark brown blouson-styled fur jacket, a brown velvet skirt and a satin blouse, the same burnished red color of her hair.

Mrs. Reagan wore an elegant long dinner gown with a gold, black and tan geometric pattern, its flared skirt banded in black.

On fashion, at least, she had the last word.

Asked earlier in the day if she felt in competition with Mrs. Gorbachev in what's been called the "Style Wars," Mrs. Reagan said she did not.

"I really think that's a little silly. I mean, there are very important things being discussed here," she said. "And what somebody wears or doesn't wear really isn't terribly important."