White China and Brown Bags. COMMENTARY: LET'S DO LUNCHEON

SOMETIMES, as I eat a brown-bag sandwich at my desk or grab a carton of yogurt after a lunch hour filled with errands, I think about a scene from my childhood: It is a weekday morning. Even before my sister and I leave for school, the dining room table is set for a party: damask cloth, pink and white Haviland china, sterling flatware, and a simple centerpiece. The occasion? My mother is giving a luncheon for a small group of friends.

There are many differences between my mother's life and my own, but at high noon the most obvious one comes down to this:

Women of my mother's generation had luncheons. Women of my generation have lunch hours.

Luncheon! How quaint the word now sounds, recalling a midday leisure unknown to millions of working women. Now that power lunches have become the latest measure of corporate status, the idea of a meal-without-a-deal - sociability with no strings - seems curiously out of date.

As a child, I loved to observe my mother's pre-party rituals: patiently preparing a favorite recipe, polishing silver, buying flowers, and getting out the Haviland - a delicate pattern with tiny rosebuds circling the rim, passed down to my mother from an earlier luncheon-giver in the family.

To a young bystander, these domestic tasks took on the air of small ceremonies, performed in honor of the soon-to-be-assembled guests. Watching my mother, I imagined a time when I too might play hostess, getting out my own good dishes to entertain friends while our husbands worked, babies napped, and children attended school.

So much for youthful fantasies. By the time I grew up, ladies who lunch had metamorphosed into women who work. Instead of gathering around a dining room table with friends for a few hours of relaxed conversation, women were joining co-workers for a hurried sandwich in the company cafeteria or the corner deli. Or they were heading out, lists flapping in the noontime breeze, to pick up dry cleaning, buy a pair of stockings, or shop for a wedding gift.

Of all the changes wrought by the women's movement, the demise of the luncheon may be one of the most inconsequential. There are, after all, pleasures in corporate sociability, and in the daily routine of breaking bread with colleagues while sharing the latest personal and professional news.

But there are tradeoffs too, and losses all around. Friendships, though still intact, are frequently put on hold. We make vague, hopeful promises to ``do lunch'' sometime - but for the most part we never quite do.

Nor do we manage to ``do dinner'' very often either. In my circle of friends and co-workers the story is the same. Our good dishes gather dust in the breakfront. Our sterling tarnishes in the silver chest. Our table linens go limp in the drawer. Instead of carefully planned parties, we settle for impromptu get-togethers, transferring home-delivered pizza or takeout Chinese from cardboard containers to earthenware plates.

As for our children, their birthday parties are more often hosted by Ronald McDonald than by overextended parents. A whole generation is growing up rarely hearing the phrase, ``We're having company.''

Even my mother and her friends are now more likely to meet for lunch at a restaurant than at home. Husbands are retired, and a noontime outing offers a pleasant change of pace - and place. As a consequence, the Haviland sits unused, tucked away in a cupboard in my parents' home, an elegant symbol of a bygone social order.

Recently my mother asked if I thought my teen-age daughter might like the Haviland someday. Gently I explained that as a college student looking forward to her own career, she might be as unlikely a candidate for daytime parties as I am.

But who knows? By the time my daughter has a family, more generous leave policies might enable parents to stay home with babies and toddlers. Then, like their grandmothers before them, young women may again find pleasure in china and damask at midday, and satisfaction in conversations not circumscribed by a lunch hour.

If so, social graces, like the rosebuds ringing the Haviland plates, will have come full circle - at least until parental-leave time is up and the brown bag returns.