The reshuffled French government began work today, and Yves Saint Laurent showed his collection for next fall. In both instances, it was like old wine served in a new bottle.

The cast of characters is virtually the same for the new government, but there is a smaller, tighter organization. With Saint Laurent the familiar signature ideas were shown but shuffled and spruced up for a fresh look.

Saint Laurent held his usual spot on the last morning of the week-long showings of ready-to-wear clothes. As usual, he had the splashiest crowd of the week, including actress Catherine Deneuve (looking splendid in a khaki green leather jacket), Paloma Picasso, designer Sonia Rykiel and Marie-He'le ne (Bootsie) Galbraith, wife of the U.S. ambassador to France.

Before the audiencearrived, a technician hung the signature of the house, YSL, in huge overlapping letters, upside down at the back of the stage. In minutes it was righted.

But you didn't need a logo to tell whose clothes these were. There were tunics, but now the familiar YSL tunic is shown over leather skirts. And the leather skirts now have a raised waistline and a broad band of color at the top that gives the effect of an obi. There are blazers, a bit roomier and longer. The coatdress, as seen by YSL this year, should be black leather with velvet lapels.

The designer has fiddled with his color palette. The long coat is back, over a turtleneck sweater and trousers, but nothing matches exactly; the colors are intentional near misses. He does this throughout the collection. For daytime clothes, a burgundy velvet sack-shaped jacket is teamed with a mulberry velvet skirt, a fuchsia plaid blouse and ultraviolet hat and gloves. In anyone else's hands it would look like a mistake. To dress up these rather casual shapes, Saint Laurent used Russian fur hats, fur prints and generous doses of obviously fake jewelry. Several of the models even wore clunky fake diamond ankle bracelets.

With all the color for day, YSL prefers a blackout for evening. The best is a short black crepe dress with a soft tie that pulls in the waist or a lean black crepe tunic and skirt edged in rhinestones.

Like other designers, Saint Laurent is up to his fingertips in black sequins. He has dipped gloves in sequins, as well as skirts, sleeves and whole dresses.

His finale was a Cecil B. de Mille production with models--almost all in black--lining the runway. Saint Laurent looked tired and nervous but pleased as he hastily walked between the lineup of models to the front of the stage and bowed. Then he kissed the hand of Mounia, his favorite model, and returned quickly behind the scenes.

One favorite client and friend of Saint Laurent who was not at his show was the Vicomtesse Jacqueline de Ribes. She was at home having everything except the wall-sized tapestries removed from three rooms of the splendid town house where her husband's family has lived since 1865. She had decided to try her hand at designing herself and had chosen the afternoon of the YSL show to show off her collection of fall fashions.

"Come and applaud loudly," the vicomtesse told designer Valentino, whose own show had been a huge success. Emanuel Ungaro came to de Ribes' show with his friend, French actress Anouk Aime'e. And in the front room, front row, leading the applause was Saint Laurent himself. "I feel more nervous for her than for myself," he said.

De Ribes' collection was small, designed mostly for evening. The clothes have a lean, aloof, aristocratic look that the vicomtesse epitomizes. They demand an extraordinary amount of poise to wear. (Also a lot of money--they range from $2,000 to $7,500.)

But it's clearly the way a lot of women want to look. Aniko Gaal of Garfinckel's and Val Cook of Saks-Jandel raved about the show. But Saks Fifth Avenue will be the first store to have the clothes in Washington.

And what of the vicomtesse's husband's reaction? "I'm very glad it's over," said the vicomte.