BRIEFLY NOTED.

Only Revolutions, by Mark Z. Danielewski (Pantheon; $26). In his new novel, the author of "House of Leaves" is up to his old tricks--multicolored and upside-down text--and some flabbergasting new ones, including a double-ended structure that obliges the reader to flip the book every eight pages. (Two place-holding ribbons are provided.) The plot involves a pair of teen-agers, Sam and Hailey, who narrate alternating accounts of a freewheeling adventure through America. Their main activity seems to be having sex in a car, though the language leaves room for doubt: "I pop lobgobs of orifice missing / globblobs, swiggling thrushrushed," says Sam. Some of the calmer passages show real talent, but there is little payoff. After all the wishfully Joycean compounds, Whitman-derived versifying, and opportunities for losing one's place (the ribbons slip off the page as easily as the gobbledygook slips from the mind), one ends up asking, with Sam, "Why for?"

Giraffe, by J. M. Ledgard (Penguin Press; $24.95). Based on the true story of the slaughter, in Czechoslovakia, in 1975, of the largest captive herd of giraffes, Ledgard's meditative novel creates a textured allegory for the country's oppression by its Communist regime. The story follows a hemodynamicist who has studied the giraffes, and a factory worker whose somnambulism is alleviated in their presence. Both are entranced by the creatures' stately aloofness, and when the order comes to kill the giraffes, which are infected with a contagious disease, they attempt to bring a measure of humanity to the workings of the state. Ledgard combines fine research with lyrical style; his description of a giraffe's astonishingly complex circulatory system is particularly memorable. The use of recurring images--mermaids, a rusalka (a Slavic water nymph)--conjures a world of fantasy and menace, balanced between dream and ...