The Brown Buffalo bellows from beyond the grave--and the roar resounds. Oscar ``Zeta'' Acosta is most widely remembered as the model for Hunter S. Thompson's drug-gobbling Samoan attorney in Fear and Loathing in Las Vegas, a masterpiece of demented reportage. The Mexican-American civil rights lawyer and political activist disappeared in Mexico in 1974; Acosta's editor and biographer Stavans (Bandido: Oscar ``Zeta'' Acosta and the Chicano Experience, 1995) suggests that he died in an accident or was murdered, but, more tantalizingly, also offers the theory that Acosta may have simply decided to vanish south of the border to acquire an Ambrose Biercelike mystique. Acosta's previously published writings include two fine books, Revolt of the Cockroach People and Autobiography of a Brown Buffalo, as well as a handful of stories, articles, and letters. Stavans adds considerably to this stock with a sampling of Acosta's acid (that is to say, both lysergic-fueled and scathing), often howlingly funny poems, a quartet of roughly shaped short stories, and a play, all of which will be welcome to students of Chicano literature and Acosta fans. Especially valuable are a handful of brown-power pamphlets and a politically charged autobiographical essay in which Acosta addresses his fellow Mexican-Americans. ``You can't be a class or a nation without land,'' he asserts. ``We have to develop the consciousness of land as the principal issue just as three years ago we had to develop the consciousness of identity as the principal issue.'' Acosta reiterates, in a madcap letter to Playboy magazine, that he can rightfully claim coauthorship of the theory of ``Gonzo journalism,'' which Thompson rode to fame: ``These matters I point out not as a threat of legalities or etcetera but simply to inform you and to invite serious discussion on the subject.'' Stavans does service to Acosta's memory and to Chicano literature, with this collection.