When Fairfax County Board Chairman John F. Herrity heard that fellow Republican Supervisor Marie B. Travesky had arranged a meeting with some of her constituents to discuss development plans for an area in her district, he sent one of his staff members to attend.

Travesky promptly threw him out.

"I called it," said Travesky, who declared that the gathering was not a public meeting. "And I told him, 'I can put those four people in my car and take them to my house.' And he said, 'Yes, I know you can.' And I said, 'But I'm staying here.' "

It was the latest chapter of a long-running feud between two Republicans who never seem to miss a chance to tweak each other. Travesky is the supervisor from the Springfield District, a post she won in 1975 after the seat was vacated by Herrity, who ran for the at-large chairmanship.

"Their violent disagreements," said one county official, "have been over piddling items, never major issues."

Nonetheless, the feud continues. Some say it rages because Herrity is more conservative than Travesky, his position is mostly ceremonial, and because Travesky refuses to walk a straight party line; others say they just don't get along. But most say they believe the conflict is simply a power struggle over who represents the Springfield District--and that Herrity would have the same battle with whoever held that seat.

"Jack still thinks he represents the district," said one local politician.

"Jack does interfere and has been doing it ever since Marie was elected," said a Springfield resident active in local politics. "He feels he knows the district better than she does, that those people were his constituents and are still his constituents. It annoys her. It would annoy me."

When asked about the friction, Travesky rolled her eyes, sighed and shook her head.

Herrity denied that he has any particular problems with Travesky. He said he has turf problems with all the supervisors, because as an at-large supervisor he must represent all of the county's 600,000 residents. Whenever he gets involved in an issue, "it's always in someone's back yard," said Herrity. Any disputes with Travesky are "not personal. I don't play personal games. That's not my style." Sometimes, however, the Herrity-Travesky feud seems distinctly personal.

Last month the supervisors discussed progress that was being made on clearing up traffic congestion at Old Keene Mill Road and Backlick Road, an area that used to be in Travesky's district, but was shifted to Democratic Supervisor Joseph Alexander's territory during redistricting.

Herrity profusely complimented Alexander's work on the project. Travesky bristled. She had spent years working on the plan before redistricting.

"I'm sorry you didn't like it the traffic plan when it was a Springfield program, Mr. Chairman," Travesky said curtly. That elicited a disgusted look from Herrity, who replied, "I always supported it." He suggested Travesky review his votes.

At another board meeting, Herrity submitted five letters from citizen organizations asking that they be given more time to work out the development plan for the Centreville area. He asked that their request be considered by the board.

Travesky, who represents the area, objected: "I was unaware of these letters until this morning." She said she called one of the groups and was told that Herrity had asked them to write the letters. She asked the board to delay any action until she had time "to get to the bottom of this." The discussion was delayed.

"The ironic thing is that Jack, when he was the supervisor from Springfield, appointed Marie to the school board," said one former Democratic supervisor. "I think it's maybe one appointment he regrets."