Jack Valenti, a Texan who was credited with giving the motion picture industry a Victorian voice and a modern outlook during his nearly 40 years as head of the Motion Picture Association of America, died Thursday at age 85 after suffering a stroke a month earlier that had left him in a comatose state. Valenti, a former presidential aide to Lyndon Johnson, became head of the MPAA in 1966 and continued to lead the group until 2004. He was regarded as the father of the motion picture ratings system and defended it with gusto throughout his tenure. In a statement, Dan Glickman, who succeeded Valenti as chairman of the MPAA, called Valenti "the ultimate leading man ... a showman, a gentleman, an orator and a passionate champion of this country." A recently completed memoir, This Time, This Place: My Life in War, the White House, and Hollywood, is due to be released on June 5.