On a sultry, slow July afternoon, a gypsy called Scarlet Rivera left her Lower East Side Manhattan flat, violin case in hand. She was heading for a friend's place to kill time before a rehearsal with an obscure 10-piece Latin band that paid her $100 a week. "Then this car comes up and cuts me off," says Scarlet, picking up the story. "Some ugly green car. The guy driving asked me if I really knew how to play the violin." He never showed his face, but the impassive profile was unmistakable. "Actually he had this woman next to him ask me," Scarlet corrects herself. "He asked her to ask me for my phone number, but I told her to tell him that I didn't give out my number to somebody stopping me on the street." No, not even to Bob Dylan. "Come downtown and rehearse with me," the Tambourine Man finally said for himself. "I'm heading uptown," Scarlet snapped and brashly requested a ride. She was beckoned in, Dylan turned downtown and hijacked her to his studio. The rest is rock legend.

Shortly thereafter, Scarlet was to become an indispensable member of Dylan's Rolling Thunder caravan, and it is her writhing, poignant improvisations that so deepen the nine cuts of his current chart-topping album, Desire. There is one other bizarre switch to Dylan's pickup. As Scarlet recalls the green car encounter, "He started making up this entire fantasy all about him being some gypsy musician named Danny who had just gotten off the boat from Hungary." Of course, if truth be told, Rivera's Romany roots are as fanciful as those of her fabled chauffeur. Scarlet comes not from an Andalusian cave but from suburban Chicago. Scarlet Rivera was born—26 years ago—Donna Shea and is of Irish-Sicilian ancestry.

But by any name, her fiddle is just as sweet, and there is gypsy—as well as blues and jazz—in her soul. Dylan, she believes, will resume his bus tour this spring, possibly in the West and Southwest. She will be along, but musically she is not content with Dylan's simple folk rock. She is trying to break out with a heavily amplified five-piece group called Mammoth. Its impressionistic jazz, rock and classical fusions reveal more dramatically than Dylan"s band could the full screeching fury of her music. "It's much more complex and powerful," she says.

Her manager, Jennings Burch, a Manhattan cop who draws charts for the NYPD and who has written material for Sacha Distel, says three major record firms are considering Mammoth for their labels. Scarlet, he says, also has a feeler to record with an ex-Beatle and Rick Danko of the Band.

If Mammoth makes it, Rivera will be one of the very few women to play lead solo with a jazz-rock band. It has been a long and bumpy climb. "Scarlet" obedientiy took up classical violin at age 7 and won numerous all-Illinois competitions. But a rebel stirred within. "The whole classical syndrome," she says, "can rob you of your childhood and happiness. The competitive attitude bothered me, when some lousy kid brown-nosed the conductor and would get first chair." So she temporarily retired from music at 15. But she found that without it the rest of high school was "a big zero. I really suffered." Right after graduation, she moved to downtown Chicago and labored variously as a secretary and "the worst waitress on earth." Scarlet later spent a year and a half at Southern Illinois University on a music scholarship but found it even more stifling than high school. "One conductor seemed more concerned with my body. I was very serious about music then and he was all involved with my hair or something." Her growing alienation led to her interest in the gypsy world—its music, readings, dances and magic. With that interest, came her change of name and increasingly exotic touches in her life-style such as wearing talismans, using herbal toothpaste and practicing the art of knife throwing. "I love the romance and the travel of gypsy life," she says. So she hit the road for the New York jazz scene, taking the scenic route, via California.

Since settling into Manhattan in 1971, Scarlet has dreamed of running off to live with a band of real gypsies in Eastern Europe. At first she could not afford the fare. Now there is a different reason, ironically, in the one area where gypsies are supposed to be rich. "The way things are going now," she smiles, "I just don't have enough time to take off and go."