When Gregor Piatigorsky, the Russian-born cello virtuoso, died last August, he left various legacies. There are his wife, the former Jacqueline de Rothschild of Los Angeles, a sculptress and chess-player, and two children - Joran, a biochemist at the National Institutes of Health in Bethesda, and [WORD ILLEGIBLE] , now Mrs. Daniel Drachman of Stevenson, Md., artist and mother of three.

There are five grandsons; a host of students, including most of the firstchair cellists in the country; decades of recordings; the Piatigorsky cup, a chess tournament; and an estate of $2.8 million, which includes two famous cellos, he "Batta" and the "Baudiot"; a house redesigned by Frank Lloyd Wright, and paintings by Chagall, Degas, Monet, Rouault and Toulouse-Lautrec.

Few musicians can boast such worldly success. Piatigorsky himself in recent years discouraged aspiring young musicians from trying to earn their livelohood through music alone. But Piatigorsky, praised by conductor Serge Koussevitzky (among others) as "the greatest cellist of our day," possessed more than musical genius. Despite a difficult childhood, described in his autobiography as a series of near-starvation disasters averted by his playing in the brothels and seedy cafes of Russia and Europe, he was characteristically able to turn his talent to success and his charm to luck.

That he married a Rothschild is of no consequence, his children insist. They say he was already established as one of the best cellists in Europe by 1937, when the daughter of Baron Edouard de Rothschild, the French financial wizard, came to one of his concerts in Paris. She was studying piano. They were married soon after.

"Legacy? I would say his students are his legacy," says Joram. "He was teaching the day before he died. He could hardly breathe, and he was teaching. MOre than anyone I've every known he gave himself to his students."

Summer afternoons spent fishing with his father, Joram believes, precipitated his own scientific career, first at Harvard, then at the California Institute of Technology. "I'd start dissecting the fish we caught," he says, "and my father always sort of imagined me as an oceanographer." He laughs. "I did write my Ph.D. thesis on the fertilization of sea urchin eggs."

There is fondness and awe in the carefully chosen words.

"He was a lot more than a cellist," Joram says. "He could have been a writer, a scientist. He really knew a lot about eels, spiders, fish and whales. He was interested in gerontology. And he wrote poetry, as well as his autobiography. He never published a poem, but you'd find them on the backs of napkins."

He left a cluttered legacy of papers to be dealt with: the poems on napkins, the amusing little stories of an imaginary "Mr. Block," the music manuscripts and the unfinished second volume of autobiography under contract, Joram thinks, with Doubleday. They fill several filing cabinets in the garage of the Piatigorskys' house in Brentwood, Calif., a suburb of Los Angeles. The manuscripts have been turned over to musicologists at the University of Southern California, under the auspices of the Piatigorsky Chair.

"He wasn't terribly organized," says Joram with a grin.

"Of course, I thought of medical school," he says in defense of pure research in developmental biology as a profession, "but no optimist who really loves life could want to seek the sickness in the same cells whose life processes he could be studying."

As for his father's cellos, Joram will not speculate upon their fate, except to say, "I have two boys, my sister has three boys. Who knows? We'd like to keep them in the family, I think."

"When we were little, my father was very modest," says Jeptha Drachman, nee Piatigorsky. What with her family - naurologist-husband who plays the clarinet, three sons ages 10, 12 and 14 - and her studio, where she paints and sculpts, she hasn't much time for interviews.

"We lived in Philadelphia when he was teaching at the Curtis Institute," she says, "and I remember at some point he was going to play. I asked him if he were any good, and he said, 'Well, not too bad.'" That was typical of him."

She, too, shies away from talk of the estate and the fine art collection and will mention only Soutine and Degas. "He was not the kind of person," she insists, "who would fix on a name and say, 'That's who I like.' She describes her mother as "a remarkable person in her own right," adding tennis and the piloting of light planes to that lady's already remarkable list of accomplishments. "He loved my mother's sculptures," she says, "and encouraged her - all of us - to do whatever we did as well as we could. They were a good pair, they got on so well together. When he was in the room, everyone turned to listen. And she was the same sort of person. It was lively, always."

Frequently, she remembers, the house was full of musicians. "Jascha Heifetz came, of course," she says, "and William Primrose, and Arthur Rubinstein was often at our house, though whether or not he actually played chamber music, I'm not sure. That would have been a long time ago. And Leonard Pennario and Lukas Foss came, and Pincus Zukerman, and Itzaak Perlman and Daniel Barenboim and Mitchell Lurie, who is less well known, but a fine clarinetist."

She says her father announced her engagement after playing the Mozart clarinet quinete with her fiance, Daniel Drachman, Heifetz and several others. "Daniel only had a B-flat clarinet and the music is written in A, so they all had to play transposed parts, and they played beautifully. My father announced my engagement like an Indian chief giving his daughter to a brave who has just fought well in battle."

And on Sunday afternoons at the Drachmans in Stevenson, there are still impromptu chamber music concerts. The children aren't quite old enough to participate, she says, but with one playing the flute, one studying the cello and one hesitating somewhere between the oboe and the piano, she is hopeful. The legacy is there.