Displaying President Kennedy's bullet-riddled clothing to help make their point, a panel of medical experts yesterday supported the Warren Commission's controversial finding that a single bullet wounded both Kennedy and Texas Gov. John Connally moments before the president's murder 15 years ago.

The spokesman for the panel, New York City's chief medical examiner, Michael M. Baden, told the House Assassinations Committee that the fatal shot that then tore through the president's head clearly came from behind.

Dismissing the conspiracy notion that the real assassin might have fired the final shot from another direction, Baden said the panel found "no evidence to support any but a single gun-shot wound of entrance in the back of the president's head."

The only dissenting not came from Coroner Cyril H. Wecht of Allegeny County, Pa., who agreed that the fatal shot came from behind, but disputed the conclusion of his colleagues that the much-maligned "single bullet" theory concerning the other wounds sustained by Kennedy and Connally was correct.

Even Wecht agreed, however, that all the shots that struck the two men in the presidential limousine came from behind them, in the direction of the Texas School Book Depository, where Lee Harvey Oswald had gotten a job a few weeks earlier.

The single bullet theory is crucial to the Warren Commission's findings because no one gunman could have wounded both Kennedy and Connally with separate shots in the chaotic, split-second interval when they were hit.

The findings have always been clouded, however, by the hurry-up nature of the autopsy performed on the president and the "near pristine" nature of the bullet that is supposed to have wounded the two men nearly simultaneously. It was found on Connally's stretcher at Parkland Hospital in Dallas after the shootings.

In understated tones, Baden reported that the panel of forensic pathologists, who have collectively conducted more than 100,000 autopsies, had found a number of deficiencies in the manner in which the autopsy was done at Bethesda Naval Hospital the night of Nov. 22, 1963.

The experts, the committee was told, took exception to the hurried removal of Kennedy's corpse from Dallas, which had a qualified medical examiner; the inexperience of the military physicians who performed the autopsy; the lack of communication between them and physicians in Dallas who initially treated the president, and the the fact that the autopsy physicians never even looked at the clothing Kennedy had been wearing.

Echoing his own chagrin at the pressures he felt in conducting the autopsy, reportedly his first ever, Capt. James J. Humes (USN-Ret.), told the committee yesterday afternoon that he never even saw the autopsy photographs or X-rays taken that night until nearly two years later.

Baden said the autopsy report Humes wrote on Nov. 23-24, 1963, had the fatal shot entering Kennedy's head near the hairline four inches below the actual point of entrance. The New York medical examiner suggested that the autopsy doctors, a team of three headed by Humes, may have mistaken a bit of dried blood for the entrance wound.

Plainly ill at ease, Humes testified later in the day that he thought the discrepancy was being exaggerated.

He said he had never precisely stated in the autopsy report where the fatal entrance wound was beyond stating that it was "above the bony occipital protuberance" in the back of the head.

"I think we're in somewhat of a semantic discussion of where it was," Humes said of the fatal wound. The important point, he said, was that "there was one - and only one - wound of entrance" in the president's skull.

The Warren Commission concluded that Oswald, acting alone, fired three shots at the presidential limousine in Dallas, one missing competely, another hitting both Kennedy and Connally and the jump seat ahead, and the final shot tearing into the president's skull.

Baden said careful examination of all the autopsy photographs and X-rays and other available evidence backed up the conclusions about how the two men were shot. A clothes dummy wearing Kennedy's torn, bloodstained suit jacket, shirt and tie, and another with Connally's garb, were brought out as supporting exhibits.

Baden said Kennedy's jacket and shirt both showed a perforation corresponding directly with an entrance wound in the president's back, this one "a bit lower, perhaps two inches lower," than where the autopsy doctors had depicted it.

This shot, the committee was told, came out through the president's neck, where the pathologists found clear signs of an "exit perforation" at the bottom of a surgical incision the Parkland Hospital doctors had made in the hopes of reviving the president.

From there, Baden said, the bullet tore into Conally's back, broke a rib, came out his chest, hit his wrist and lodged, spent, in his thigh. The pathologist found no significant metallic fragments in Conally's thigh bone.

"It did not penetrate more than a half inch or so [into Conally's thigh] and it was not present" when the governor underwent surgery at Parkland, Baden reported. "The panel!" he said, "concluded . . . that the bullet had partially entered the thigh and dropped out."