Ailing Maryland Gov. Marvin, Mandel will transfer a limited amount of his power to Lt. Gov. Blair Lee III, according to an informed source.

An agreement was worked out yesterday during an hour-long meeting between Mandel and Lee in the governor's hospital room at Prince George's General Hospital, the source said.

The transfer, it was learned, will be limited to brief, official functions and will leave Mandel in control of most of state government while Lee performs a few duties as a figurehead during the governor's absence from Annapolis.

The first such duty apparently will occur Friday when Lee will serve as acting governor during a regularly scheduled meeting of the state Board of Public Works. Mandel normally serves as chairman of the board.

Lee refused to comment on the move. He has scheduled a press conference for 9:30 a.m. today to discuss his meeting with the governor.

Mandel, who doctors say apparently has suffered some form of brain lesion, has been under pressure to name Lee as acting governor ever since he was hospitalized April 5. He has refused to do so, except for one two-hour period last Tuesday during a formal bill signing ceremony.

The midafternoon meeting yeterday apparently was the first time Mandel has seen anyone except doctors, nurses and members of his family since he was hospitalized eight days before his political corruption trial was scheduled to begin.

The only contact he has had with Lee and other state officials has been through messages delivered him by his wife, Jeanne and state troopers stationed outside his room on the ninth floor of the hospital in Cheverly.

This has led to some murmurs of discontent, but officially Mrs. Mandel and Lee have remained on good terms.

The pressure to turn over additional authority to Lee, who assumed many of the governor's informal lobbying duties during the final days of the state General Assembly, increased last Wednesday when Mandel's political corruption trial was delayed for one month because of his illness.

At several points during a hearing on a motion to delay the trial, chief prosecutor Barnet D. Skolnik pointedly asked how Mandel was well enough to continue his duties as governor, but not well enough to stand trial.

The 60-year-old Lee, who is expected to be one of the candidates in a crowded Democratic primary for governor next year, is taking his limited time as "acting governor" with his usual conviviality.

Interrupted during his dinner at the hight, Lee said only that he and the governor "did not discuss anything cataclysmic" during their one-hour meeting.

Lee would not comment on the report that his next limited assignment will be to preside at Friday's works board meeting, noting that he had promised Mandel's press secretary, Thom L. Burden, that he would not "breech the integrity" of his Tuesday news conference, "especially to reporters of the Washington Post and Baltimore Sun," Lee laughed.

At the works board meeting last week, Comptoller Louis L. Goldstein and Treasurer William S. James shared the duties. With Mandel missing, it was left to those two officials to decide on dozens of contracts awarded by the state, including a $40 million construction job on the fledgling Baltimore subway system.