Who is C. L. Byrd? Well, the publisher isn't saying. But any reader who plows through this long, jumpy, sporadically amusing mess of a novel will figure that ""Byrd"" is at least two people--because what starts out as a sassy, tight immigrant saga soon becomes a chic, cartoony hash of 1960s art-world relationships (heavy on casual/kinky sex) . . . and winds up as a dreadful mix of trendy soap-opera and ludicrous psycho-melodrama. The setting throughout, more or less, is Manhattan's downtown ""Soho"" area--known as ""The Valley"" back in 1913, when little immigrant Eli Dansky arrives in N.Y. with tubercular mama Leya. Eli is soon working at cousin Zelig's button factory on Greene St., carrying on with a sexy widow, becoming Zelig's right-hand man by the '30s. And when Zelig offers Eli a partnership if he marries one of Zelig's daughters, Eli yearns for underage Sophie, romps with racy Molly, but weds quiet Mae; and by 1940 Eli is buying up loft buildings and philandering (Mae's been cold ever since she learned that Sophie was Eli's first choice). Familiar Jewish-family material? Yes, but it's all dished up with unsentimental zest and grandly authentic dialogue. Then, however, it's suddenly the 1960s--and instead of the firm central-character focus of Eli, we have an uninvolving merry-go-round of people and plots. There's Eli's niece Rochelle, who works for a Madison Ave. auction house, gets involved with shady dealings (including a murder coverup), and goes honkers. There's Rochelle's roommate Camille, who sleeps with raunchy Soho artist Dan Rainey, is quasi-raped by Rainey's angry wife, then takes up with Eli's foul son Stuart, the ""lease maven"" (an S/M/group-sex aficionado), and is last seen as a lesbian Soho restaurateur. There's Camille's friend Annie, an artist from Minnesota who lives illegally in a Dansky loft, gets involved with anti-museum radical Eliot, has an abortion, and then gets pregnant by Eli's nice son Jeff. Plus: LSD-tripping cousin Joy, age 14; Eli's longtime extramarital affair; and family business feuds. And finally, come 1974, Eli and his sons argue about loft-conversions (profitable but unfair to artists), Jeff and Annie finally get together . . . and Eliot turns out to be not only Soho's psycho-arsonist (driven by devil voices) but also Eli's son--from his first extramarital affair! Sounds like a parody? So it does; and perhaps Byrd--who is strongest on satiric art-world details and acerbic dialogue--should have found a more overtly comic format for the Sixties material here. As it is, with reams of explicit sex, oodles of insider allusions, and arbitrary nods to the saga format, this is a garish hybrid which will consistently please none of its potential audiences: savvy New Yorkers, fans of Jewish-family fiction, or commercial-saga regulars.