"The bull is more than just a symbol to Larry Speakes," went the joke around the White House last week, before he resigned as communications director for Merrill Lynch.

On Capitol Hill, other jests made the rounds. After news of the resignation arrived, this one began circulating: "Is he resigning for himself or for Ronald Reagan?"Since he disclosed in a new book that he had fabricated presidential quotes to feed a news-hungry press, the capital has been abuzz with Speakes quips and anecdotes.

For instance, when Tom Pettit, chief national affairs correspondent for NBC News, appeared before editors at the American Society of Newspaper Editors meeting in Washington he said he had sought Speakes' counsel before his speech.

"He told me, `First, be sincere.' " Pettit said.

President Reagan, in whose name the concocted quotes were made, showed his own sense of humor about the flap when he addressed the editors' group.

"I've told this story before," Reagan said, "and if you've heard it, I hope you'll just bear with me.

"That's the nice thing about this job. You get to quote yourself shamelessly, and if you don't, Larry Speakes will."

Reagan's jaunty reference contrasted with his stern "no comment" later Friday to reporters asking about Speakes as the president boarded a helicopter for Camp David.

Reagan's different reactions reflect an ambivalence in political and journalistic circles about the gravity of making up quotes and attributing them to a congressman or senator, a Cabinet official or a president.

The practice of concocting quotes for one's boss is so common among press secretaries that Speakes' acknowledgment that he had put words in Reagan's mouth at the Geneva summit with Mikhail S. Gorbachev created only the barest ripples in some political circles.

Jimmy Carter's press secretary, Jody Powell, said he was only "mildly surprised" by the revelation.

"The semihysterical reaction to it has been a little bit more of a shock to me than the revelation was," said Powell, who also conceded, as Speakes has, that it was not "a proper thing to do."

Many press secretaries and reporters began their daily contacts last week with some variation of the following conversation:

Reporter: "I'm trying to work up a story on the Silver Haired Congress meeting. I'd like something from the congressman, but don't make it up."

Spokesman (feigning indignation): "Would I do a thing like that? I'd get skinned if I ever made up a quote."