Since it includes septuagenarians who have figured in the art world for 40 years, the recently unveiled Whitney Biennial can hardly be called avant-garde. But with new names and trendy ''slacker'' art, it's not precisely apres-garde either. Call it middle-of-the-road-garde.
The every-other-year survey of the latest movements in contemporary American art on display at the Whitney Museum (until June 4) looks like a fence straddler this year. With an all-inclusive theme of ''metaphor,'' it's got something to attract -- or repel -- everyone: a mishmash of minimalism, conceptual art, gestural abstraction, figurative painting, and censorship-flouting photography (like Catherine Opie's portraits of transvestites).
Four floors of work present 89 artists, including new developments in video. One observation emerges from the multigenerational cast. Once the initial shock is past, hot stuff has a way of becoming ho-hum stuff -- unless it embodies more than the ''shock of the new,'' as Robert Hughes calls it. Parts of the show inspire a been-there, seen-that, time-to-move-on sentiment. For starters:
* Minimalism looks passe, as evidenced by Barry Le Va's floor arrangement. His cylinders and rectangles look like K-Mart knock-offs of the late Donald Judd's elegant geometry.
* Conceptual art, exemplified by Lawrence Weiner's cryptic wall texts, seems both overblown and anemic.
* Sublime as they appeared once upon a time, the stripped-down, purely formalist abstractions of Agnes Martin and Robert Ryman lack cutting-edge sharpness.
* Installations, judging from Jason Rhoades's room-sized concatenation of doughnuts and garage-sale odds and ends, look like much ado about nothing.
In contrast, yesterday's renegades who show real staying power are the abstractionists Brice Marden and Richard Serra. Serra's five-ton ''Primo Levi,'' a forged steel sculpture shaped like a staple, radiates muscularity. In Marden's painting ''February in Hydra'' wavy lines interweave with balletic grace as contemplative as the Chinese calligraphy it recalls. Cy Twombly's painting ''Untitled (Gaeta)'' looks like the progenitor of assembled art, much of which fuses abstract and figurative elements. Twombly's triptych includes his trademark elements: partially effaced scribbles, ascending boatlike forms, and waves of paint resembling the primordial sea.
One of the older artists represented is Jane Freilicher, whose ''View Over Mecox (Yellow Wall)'' transforms a realistic scene (a glimpse of landscape through a window) into a study of form. A slab of wall and wedge of windowsill yield to color bands of lawn, salt marsh, and bay.
Milton Resnick, known as an Abstract Expressionist, also bridges the figurative and abstract with ''Woman,'' a heavily impastoed oil in which a goddess seems to be both dissolving into the canvas and emerging from it.
The best-of-show category prize goes to photography, with the most consistent winners of any medium.
Cindy Sherman continues her explorations by playing with dolls. She mixes anatomical parts of maimed mannequins for an unnerving visceral effect. Judy Linn's black-and-white prints present quirky snippets of daily life. Jeff Wall's panoramic, backlit ''A Sudden Gust of Wind'' inspires an open-mouthed sense of wonder, as in the last scene of Fellini's ''Amarcord,'' in which a blizzard of white petals engulfs an outdoor wedding.
Nan Goldin, a repeat contender from past biennials, documents denizens of Tokyo's sleazy demimonde. In her lush color portraits, which take up a whole wall, people wear fishnet clothing or nothing but rings in their flesh. What draws you in is not all the exposed skin but how exposed the faces look: not happy but not sad either.
John O'Reilly's montages are the discovery of the show. An almost complete unknown, the Massachusetts artist's ''Series of Benjamin Britten'' mixes photo fragments of soldiers with scraps of fine-art reproductions. One GI has the body of a crucified Christ. Another is comforted by a Renaissance angel.
Punk cartoon art is overrepresented in the show. Examples are Lari Pittman's spoofs of consumerism and Christian Schumann's adolescent doodles.
In the show's catalog, curator Klaus Kertess states his goal -- to recapture the experience of art's sensuous beauty. Examples are Philip Taaffe's Byzantine-pattern paintings and Catherine Murphy's ''Curtained Window,'' both blends of semirealistic and abstract styles. The danger with this emphasis on color and form is that it can easily slip into the realm of pretty decor.
The last Whitney Biennial was roundly criticized as a political harangue for its in-your-face stridency. This year the only works likely to startle and amaze are baroque assemblages by Nari Ward and Nancy Rubins.
Ward's ''Peace Keeper,'' a real hearse covered with tarry resin, sits in a barred cage, atop a heap of rusted pipes and below an overhead suspension of mufflers. It's a spectacular evocation of mortality, especially with the mufflers looming above.
Rubins also hangs ordinary objects in the air. In ''Mattresses and Cakes,'' she crumples 150 mattresses, with layers of cake and frosting inserted in the crevices. ''It's the icing on the cake of the show,'' as one wag said.
Nicole Eisenman has the last word. Her mural reveals mixed emotions about the show, with all its media hoopla and ability to make, break, raise, or sink reputations. ''Self-portrait with Exploded Whitney'' shows the museum reduced to rubble. Reporters swarm over the ruins as artists weep and expire. Behind the disaster scene, her back to the crowd, Eisenman sits calmly painting. After the chaos and publicity, she seems to say, an artist goes on making art.