And author Djuna Barnes was furious when Gertrude, rather than commenting on her writing, said she had beautiful legs. Adrienne Monnier, owner of La Maison des Amis, and Sylvia Beach, owner of Shakespeare and Co., themselves a couple for 38 years, took issue with the infamous treatment at 27 rue de Fleurus of visiting wives, who were expected to talk of hats and cuisine with Alice while the men and Gertrude held forth on literature. Any woman who dared stray into the men's conversation was soon dragooned by Alice into the kitchen, or forced to comment on some small household object.

As for children, Gertrude and Alice adopted many. They took in impressionable young modernist writers -- like Fitzgerald, Hemingway, Sherwood Anderson and Paul Bowles (Gertrude suggested that "Freddy" was a better name for him and refused to address him by any other name).

They also had dogs, who mostly sat on the lap of Mount Gertrude. (Gertrude claimed that the rhythm of her dog Basket's breathing taught her the difference between sentences and paragraphs.) The menagerie of canines, little and large, included Polype, a hound who enjoyed eating his own excrement nearly as much as he enjoyed smelling flowers; Byron, named for his sexual interest in his mother and sisters; Pepe; and Basket the First, whom Gertrude insisted be bathed in sulfur water each day. (She also insisted that Paul Bowles put on a pair of lederhosen and run the dog dry while Gertrude called out the third-story bathroom window, "Faster, Freddy, faster!") They also had a cat with a mustache, named Hitler.

With their closest friends, Gertrude and Alice created small nuclear families, at least through the terms which they chose to address them. With Carl Van Vechten, the famous photographer and not-so-famous writer, they formed the Woojums family: Carl was Papa Woojums, Alice was Mama Woojums, and Gertrude, the child savant, was Baby Woojums. During World War I, they adopted a young American G.I., whom they called Kiddie, and who remained in close contact with both women throughout their lives.

As commonplace as Gertrude and Alice's marriage was in its general outline, the detail was, obviously, remarkable. Perhaps the most extraordinary part was the fame. Gertrude and Alice became famous. Stunningly, iconically, rock-star famous.

And, bizarrely, when it happened, the marriage itself became invisible.

"The Autobiography of Alice B. Toklas, " Gertrude's love letter to Alice, became one of the unlikeliest blockbuster novels of all time. It is possible that the book's astounding popular success had more to do with its cast of characters -- Picasso, Hemingway, Rousseau, Picabia -- and the implication that two Americans were at the Parisian epicenter, than with America's appetite for experiments in modernist literature.

Nevertheless, when Gertrude and Alice returned to America for Gertrude's book tour in 1934, they made the front pages of the major New York papers, and a revolving billboard in Times Square spelled out in lights, "Gertrude Stein has arrived in New York."

Alice, described coyly as Gertrude's "constant companion," appeared in all the published photos with Gertrude. Alice topped her outfits with a feathered chapeau; Gertrude wore a deerstalker cap; each wore a pair of Mary Janes. They were interviewed together in their shared hotel room and recognized by strangers while out grocery shopping.

And yet no one commented on the strangeness of a pair of middle-aged lesbians becoming the media darlings of 1930s America. And when they started to do so -- years later, when Alice was left alone to fight Gertrude's would-be biographers -- Alice refused to speak to anyone who she believed would delve into her lover's private life. She preferred to keep her love as it was, an open secret.

"I am nothing," she said, "but a memory of her."

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