Metro subway trains don't have conductors who roam the cars collecting tickets and calling stations, but a Metro passenger satisfied his Walter Mitty fantasy Thursday evening, acting a conductor's role. He walked the aisle, making an announcement that caused a near total evacuation of the last car of the four-car train at Rosslyn, the junction of two lines.

To take it from the top:

A Virginia-bound Metro train, passing through downtown Washington, bore those esthetically nauseating dot-matrix destination signs -- the ones that make the trains look like roving savings and loan branches -- that said, more or less plainly, that the train was on the Orange Line destined for West Falls Church. (Some trains on the line, which has its terminus at Vienna, tie up for the night in a storage yard at West Falls Church.)

But boarding passengers were told by the operator over his amplifier system, "This is a Blue Line train for National Airport."

Blue Line for National Airport? Orange Line for West Falls Church? Who, or what, does one believe?

Our Mitty-minded passenger went to the emergency call box at the end of the last car of the train and pushed the button to call the operator. "Your destination sign says West Falls Church but you're announcing Blue Line, National Airport," he told the operator.

"Ignore the sign," replied the operator, "This is Blue Line to National Airport." But the operator didn't take the next step and announce that fact explicitly and plainly over the public address system to riders who, if they're regulars, tend to tune out announcements made to boarding passengers. The regulars expect the train to go where the destination signs say.

Mitty's man walked down the aisle as the train approached Rosslyn and called out, conductor-like, to a befuddled carload of passengers, "This train is a Blue Line for National Airport. The operator says the sign is wrong. Change at Rosslyn for the Orange Line."

Passengers in that car walked out en masse, an exodus not matched by the other three cars of the train. One wonders what the misdirected Orange Line passengers in those cars thought when they embarked at, presumably, Pentagon station to work their way back.

P.S. -- On leaving Rosslyn for National Airport, the train signs had been changed to "Special." Downtown Parking Problem

Look whose car was parked for nearly an hour on an expired meter yesterday in downtown D.C. Hint: It bore Maryland tags with the words, "MAYOR -- CITY OF BALTIMORE."

Mayor William Donald Schaefer's driver found the scarce space out front of The Washington Post building, where the mayor had come for an interview to press his candidacy for governor of Maryland. His driver had the good grace, or good sense, not to try to extend the original paid period by feeding the expired meter: that is a law violation, too.

Although no meter attendant drove past during Schaefer's hour of violation, would he have gotten a ticket? Would Mayor Marion Barry have gotten one? Would you have gotten one? Is there, as chiseled on the Supreme Court building, Equal Justice Under Law?