"These jazz guys can be pretty loose, but not showing up was going a bit too far." That's what one Wolf Trap official, who did not want to be identified, said yesterday about pianist Oscar Peterson simply not showing up for his Sunday night performance. It was a double blow to jazz fans since singer Ella Fitzgerald had been forced to cancel earlier because of a foot infection. The legendary jazz singer Carmen McRae had rushed to Wolf Trap to substitute for Fitzgerald.

After McRae performed, an announcer explained with obvious irritation in his voice that the audience of some 4,000 could have their money back since Peterson had not shown up. That could cost Wolf Trap about $50,000. Matt Hessburg, a spokesman for Wolf Trap, said yesterday that no one knows yet what happened and there is concern about Peterson's whereabouts. When the Wolf Trap limo went to Dulles early in the afternoon to meet his flight, he wasn't on the plane. When Peterson's management, Salle Productions in Los Angeles, was called, Wolf Trap officials say, they were told Peterson has never missed a scheduled performance. Peterson was not on any later planes. As of late yesterday afternoon, there was still no explanation. Hessburg said it was the first time in Wolf Trap's 17-year history that both scheduled performers canceled. Morris for President

You know it's August in Washington when things get a bit sillier than usual, so why not have a famous cat announce for president? Morris the Cat of advertising fame is to announce his bid for the Oval Office at a news conference at the National Press Club today. He'll run as an independent. And since it's August, Morris will probably get good coverage. Most of the talking will be done by his campaign manager, Eleanor Mondale, the daughter of the former vice president who didn't make it to the top job. Morris ought to be thinking about that.

And, since this is the era of public opinion polling, the 9-Lives cat food company (the special interest group behind Morris) actually hired Opinion Research Corp. to determine the celebrity cat's recognition factor. Morris came in at 70 percent, ahead of hopefuls such as Sen. Robert Dole, 67 percent; Reps. Jack Kemp, 59 percent, and Richard Gephardt, 53 percent; and former Arizona governor Bruce Babbitt, 33 percent. Maybe the electorate will appreciate his ethical stand, "I may shed, but I don't shred." Out and About

Larry Bond, the man who received little credit for "collaborating" with bestselling author Tom Clancy in the computer war-games-in-print novel, "Red Storm Rising," has signed with Warner Books for a major military scenario novel set in the Far East and Pacific Rim. Bond is a former antisubmarine technology expert and naval intelligence officer. In the introduction to his paean to military technology, "Red Storm Rising," Clancy acknowledged that the idea for the book came from Bond and that they had collaborated, but Bond did not get a book jacket credit ...

Rock star Gregg Allman was back on the road yesterday after checking into Roosevelt Hospital in New York complaining of chest pains. The 39-year-old Allman, famous for having drug problems and a turbulent marriage to Cher, was stricken in his Manhattan hotel room and taken to the hospital by ambulance. He was released a few hours later to continue his concert tour. Hospital officials declined to report on his health ...

For Tom and Jerry cartoon fans, history is about to be made. Turner Entertainment and Hanna-Barbera Productions have announced plans for the first feature-length Tom and Jerry cartoon for release in theaters. Created by Bill Hanna and Joe Barbera nearly 50 years ago, the lovable cartoon-characters have starred in shorts that have won seven Academy Awards. The film will also be the first feature-length movie for Turner Entertainment, a subsidiary of Turner Broadcasting System Inc., owners of the 276 original Tom and Jerry MGM cartoons ...