Lauren Bacall came breezing into Arthur Schlesinger's East Side town house last night, and threw her head on the nearest shoulder. "I'm terribly depressed," she said, "I'm just in a real funk after last night."

Around her were plenty of sympathizers: author Teddy White, newscaster Eric Sevareid, New York Times publisher Punch Sulzberger, columinist James Reston, Boston Globe editor Thomas Winship, Chicago Sun-Times editor James Hoge, author Lally Weymouth, Washington Post Company chairman Katharine Graham and Clay Felker, now of the New York Daily News, Gianni Agnelli, president of Fiat, provided the foreign air.

But even though Ted Kennedy was a candidate this year, the talk was more about how the guests' lives had touched his brother's. "These are the people who nurtured Jack Kennedy," said Eames Yates, a young producer at ABC.

Aside from that, everybody was warbling on about summer homes -- renovations, locations, parties given, etc. This weekend, you could probably find this crowd around wicker chairs somewhere in the Hamptons. Last night, though, the decor was a marble fireplace, three big bay windows with a vase of yellow day lilies and a backyard city terrace with ivy. There were no clouds in the sky. Mingling Among Picassos

This guy was nuts," said a fat woman in a red dress. "I think his mother didn't tell him the facts of life."

As she spoke she contemplated the Picassos around her at the Museum of Modern Art, scene of last night's reception in honor of the vice president and Joan Mondale. He didn't make it, but she did, floating through the three floors in that turned out to be a very private viewing of the exhibit that is mobbed with commoners during the day.

Some comments from the crowd:

"Now what do you suppose is going on here?" said a woman in a sparkling dress who was looking at a drawing of two nudes.

"Exactly what you think," said a woman in a polka-dot dress.

"Hahahahahahahahahaha," said a man in a pin-stripe suit who was with them. The took pictures until the guard told him to stop.

"to me, that's two people ah . . ." said the woman in the polka-dot dress, looking at a human embrace. "Two people frenching," said the pin stripes. He peered more closely. "No, maybe three people."

This party was sort of a non-party, the reason being that the Museum of Modern Art is a sprawling place where people can get lost in nooks and crannies. Consequently, there was no rumbling party center and if you weren't careful, you could find yourself face-to-face and all alone with some grotesque Picasso. But there was solace on the sixth floor, where there was food, drink and a view. Over by a Roy Lichtenstein, a young man was having a drink with a young lady and talking about his ex-wife. She was talking about her problems with men.

Among the other guests were Mayor Koch, Averell Harriman, Smith and Vicki Bagley, Nathan Landow, Democratic National Chairman John White, Sen. Claiborne Pell of Rhode Island and the Livingston Biddles. Women's World

Betty Friedan drifted under the twinkling lights of Tavern on the Green in Central Park, a wineglass in her hand and an orchid on her shoulder. "I am floating on the clouds," she said. "We took on the establishment and we made the establishment say 'aunt.'"

She was talking about the women's platform victory at the convention yesterday afternoon. So was most everyone else who filtered into the restaurant's garden for what was billed as a "Salute to Democratic Women for All Decades." This amounted to 80 of them, all honored by the National Federation of Democratic Women.

Among the guests: Phyllis George Brown, assistant education secretary Liz Carpenter, presidential adviser Sharah Weddington, ACTION director Mary King, her husband Peter Bourne and liberal Rep. Elizabeth Holtzman (D-N.Y.)

"Fabulous speech," she said of Kennedy's address to the convention last evening "I was very proud to be a Democrat."

Among the lesser known faces honored last night was Mary Aikins Currie, who's been named the outstanding Democrat of Indiana. She's also a guest of the convention. It's her third one.

"You been to one, you been to all of them, you know," she said. "And on a convention floor you can't hear half of it. I told them next time I was going to sit in my living room with the television, a comfortable chair, a drink and the air conditioner." The Ape at the Apex

Actress Carrie Fisher came to the party on the top of the Empire State Building with songwriter Paul Simon, but he temporarily deserted her. She was left to fend off the press by herself.

"Ms. Fisher, how do you stand on rent control in the city?" somebody yelled from the horde.

"I don't stand too well on anything." she said, "including my shoes . . . Where is Paul? I'm going to kill him.

In the crowd was actress Margot Kidder, a friend of hers. "Is Carrie freaking?" she asked. Not entirely perhaps, but some reporters from the Children's Express newspaper looked like they were close.

"Hey, could you arrange to get us pre-screening tickets?" said Justin Greene, a 12-year-old reporter from the newspaper who has seen "The Empire Strikes Back" five times and apparently does not worry about accepting favors from sources.

All this was occurring at a $30-a-head fund-raiser for congressional hopeful Mark Greene late last night and early this morning. Hundreds of people and one person dressed as King Kong wandered around the observation deck of the Empire State Building rubber-necking at Gilda Radner, who was the main draw. But it was hard to see her because she was being suffocated by reporters who were asking her about life after "Saturday Night Live."

"One of the most important things about show business is taking the next step," she said. "The easiest thing to do would be to remain on 'Saturday Night Live' . . ." The rest of this thought was drowned out by flashbulbs.

Among the other people that you could gawk at: Rep. Mo Udall (D-Ariz.), consumer activist Ralph Ander, Rolling Stone publisher Jann Wenner, singer Harry Cahpin and "Saturday Night Live" producer Lorne Michaels.

Chapin and Michaels had wedged themselves outside next to the railing overlooking the Garment District and the Hudson River. They were taling about the evils of Exxon, why intelligent people shouldn't vote, and nuclear disarmament. Chapin was actually doing most of the talking, which he usually does.

Then he started in on Mark Greene. "We've got a whole society that can't function," Chapin said. "But the people with fire in their bellies, you've gotta go with them. Mark's like that."

King Kong moved through the crowd. Alphabet Soup

On Monday, Mayor Edward Koch had congressmen from the A through M states over for a muggy garden party. Yesterday, the N through Z's came. Muggy again.

Confusing, too. "Oh, no," said a stricken Rep. Peter Kostmayer from Pennsylvania, "I'm at the wrong party. Oh, it's by state? Whew." The violins sang on.

So did the party, which for one reason or another had a particularly lively air. Maybe it was because the temperature was 90 instead of 100, maybe it was because lots of people had slept in after a late night Monday, but probably it was because the real business of the convention was done.

"I've got a lot of free time," said Albert Shanker, Kennedy delegate and president of the United Federation of Teachers.

"Seems to be all over but the shouting," said Jody Merritt, an airline stewardess who was holding, but not wearing, a pair of diamond-studded punk sunglasses.

The decor: Icy blue walls, crystal chandeliers, potted palms in the corner, violins that played Beethoven, and members of the local power structure. Included were former deputy mayor Peter Solomon and Peter Goldmark, executive director of the Port Authority. He's trying to settle a commuter train strike, but the union walked out Friday so now he's going to parties.

"I just got back from France," he said, spending two weeks explaining why a major American party nominated a movie actor. To them, it's like if Maurice Chevalier is running for president of France. They think we're stark raving mad." Dealing at the Tavern

Under the sycamore trees at Tavern on the Green, black delegates were sitting in white wrought-iron chairs and looking elegant. The Communist Workers Party, which has attended an impressive number of receptions this week, was screaming at them.

"Champagne blacks!" yelled one woman.

"I thought there was going to be some form of entertainment -- soft music, violins or something -- but much to my surprise we've got chanting and speech-making," said Margaret Ware, a public relations consultant from the West Coast. She reflected a moment, dragging from her cigarette. "The mere fact that they're here makes it seem like it must be a very important party."

The party was thrown by E.F. Hutton, who said it was good for business. Ben Brown, deputy chair of the Carter/Mondale committee, came and so did Mayor Marion Barry. Barry didn't wear a tie, but the capitalists in evidence did.

"I have no politics," said Dan Hall, an Atlanta investment banker with a delicious Southern accent. "I do deals."

At this point, Phyllis Landrieu, the HUD secretary's sister-in-law, wandered up. She's been buying lots of jewelry this week. "I'm on the arrangement committee of the convention, so I'm just partying," she explained. a"The arrangement committee gives me a nice place to sit at the convention and a pass to the VIP lounge which is where all the action takes place."

Hall smiled. "I gotta motivate," he drawled pleasantly. "I see a potential client." Kids' Stuff

"I'm pretty rowdy," said Suzanne Rogers, the 14-year-old daughter of a California delegate, "but I didn't think adults could be that rowdy." Her braces flashed in the sun.

This assessment was rendered at a swimming and picnic party for delegates' children, which is yet another species of the gadzillions of parties that the New Yorkers are throwing this week. Everyone seems to be holding up fine.

This event was given by the Manhattan Plaza, a subsidized housing project on the West Side. Neighborhood kids sang "Consider Yourself at Home" on an outdoor basketball court that was hot and windy, and Annie from the Broadway musical sang and ate a hotdog. She claims to have no political views.

"I don't even know what you're talking about," said Annie, who really is 10-year-old Alison Smith, when questioned about the election, "I was just here to sing."