Bobby Abbo, local restaurateur and sportsman, arrived at Laurel shortly before the fifth race opening day and strode briskly to the window to bet a 14-to-1 shot named Flying L.

"There were two or three minutes to post time," Abbo related, "and I said to myself, 'No problem here.' But the woman at the window was calling out a lot of exacta combinations, then pulled out a newspaper and studied it, then said to the seller, 'No, no, no, I didn't mean that.' Finally, she opened her pocketbook and took out the money, but put it back and starts calling out more combinations.

"She said to the seller, 'Are these good numbers?' and they started chatting. By now, it was almost post time. I didn't want to scream, but I was going nuts."

Abbo finally stepped up to the window to call out, "Twenty to win on No. 2, $2 exacta wheel top and bottom," but it was too late. He was shut out. As a horse named Eagles Reason sprinted off to a five-length lead, the seller told Abbo, "Look, pal, you saved money." But then Flying L. began to rally along the rail, accelerated strongly in the stretch and won by a length. He paid $30.80, the exacta was worth $234 and Abbo's day was understandably ruined.

Some such annoyances are probably inevitable at a racetrack, as thousands of people attempt to interact with each other in a relatively small physical space. But they happen far too often because many inexperienced bettors don't realize that there is an unwritten code of conduct at the track.

At the outset of a new racing season, it might be appropriate to review some of the cardinal rules of racetrack etiquette.

A horseplayer should go to the betting window with his money in his hand and with his wagers already decided. If he is going to play a number of exacta or triple combinations, he should have them written on his program.

When someone in front of me is still consulting the Racing Form as he wagers, I believe in issuing a well-modulated but sharp rebuke: "There is one minute to post time! This is no time to do your handicapping! Other people are waiting to bet!" Occasionally, the bettor's response will be something on the order of, "Simmer down and shut up, you jerk," but most often he will feel properly chastened and (I hope) will have learned a lesson.

It is easy for a gambler to become so absorbed in his own activities that he is oblivious to the sensibilities of the people around him. This is especially true when he is rooting during a race. All of us like to yell and cheer for our horses, to exult or curse when the results are known. But there are limits.

Last winter, at Gulfsteam Park I was standing next to a young man who yelled for his horses in the stretch drive with the sort of urgent tone one might use when pleading with the Mau-Mau to spare one's family. His behavior would have been acceptable if he had been about to win $46,000, but he was holding one $2 ticket on an exacta that was worth $46. I had to take the kid aside and tell him the Beyer Rule of Rooting: wildly emotional cheering is permitted only when the potential winnings equal 10 percent of one's annual income.

But if a horseplayer loses 10 percent of his annual income, or if he faces the loss of his home and his marriage because of an unfortunate photo finish, gross displays of emotion are still impermissible. A gambler is supposed to take his losses in stride. In the face of adversity, he is supposed to head toward the nearest bar and brood privately rather than make an ugly public outburst.

Perhaps the most difficult question of racetrack etiquette, one which can trouble even veteran horseplayers, concerns the solicitation of tips and information. May a relative novice ask an expert handicapper or an insider whom he likes in a race? How should he show his gratitude if the horse wins? How should he respond if he bets a week's paycheck and the horse runs last?

A novice should never buttonhole an expert and demand to know whom he likes in a race; the expert may have put hours of work into his handicapping and want to keep his opinions private. A casual, "Do you like anybody here?" conveys the proper tone.

If the expert shares his opinion, and the horse loses, the novice may only offer sympathy. If the horse wins, the beneficiary of the information should shower the expert with praise. If he has won a substantial amount of money, he should offer some tangible expression of thanks, such as an invitation to dinner at a fancy restaurant. (Offers of money are appropriate when the expert happens to be in a temporarily impoverished state, but are otherwise not appropriate.)

At Belmont Park this fall, a stranger approached me before the ninth race and asked whom I liked in the triple. With characteristic openness and generosity, I told him, "Bet the 2-3-5." I played the combination in precisely that order, and came away emptyhanded when the 3-5-2 triple paid $800.

The next day, I bumped into the same man. "That was a nice one yesterday," he said. "I boxed the triple for $10 (and had thus won $4,000). You must have made a big score."

"Nope," I said. "I didn't make a dime."

Did the stranger, realizing the injustice of the situation, respond by saying, "I'm sorry; please take this $200 and have a lavish dinner at La Caravelle tonight as my gesture of thanks"?

No, he did not. He demanded to know, "What should I bet in the triple today?"

Even Emily Post could not have objected to the string of expletives that constituted my response.