The autopsy examination further disclosed that, after entering the President, the bullet passed between two large muscles, produced a contusion on the upper part of the pleural cavity (without penetrating that cavity), bruised the top portion of the right lung and ripped the windpipe (trachea) in its path through the President’s neck.[C3-165] The examining surgeons concluded that the wounds were caused by the bullet rather than the tracheotomy performed at Parkland Hospital. The nature of the bruises indicated that the President’s heart and lungs were functioning when the bruises were caused, whereas there was very little circulation in the President’s body when incisions on the President’s chest were made to insert tubes during the tracheotomy.[C3-166] No bone was struck by the bullet which passed through the President’s body.[C3-167] By projecting from a point of entry on the rear of the neck and proceeding at a slight downward angle through the bruised interior portions, the doctors concluded that the bullet exited from the front portion of the President’s neck that had been cut away by the tracheotomy.[C3-168] Concluding that a bullet passed through the President’s neck, the doctors at Bethesda Naval Hospital rejected a theory that the bullet lodged in the large muscles in the back of his neck and fell out through the point of entry when external heart massage was applied at Parkland Hospital. In the earlier stages of the autopsy, the surgeons were unable to find a path into any large muscle in the back of the neck. At that time they did not know that there had been a bullet hole in the front of the President’s neck when he arrived at Parkland Hospital because the tracheotomy incision had completely eliminated that evidence.[C3-169] While the autopsy was being performed, surgeons learned that a whole bullet had been found at Parkland Hospital on a stretcher which, at that time, was thought to be the stretcher occupied by the President. This led to speculation that the bullet might have penetrated a short distance into the back of the neck and then dropped out onto the stretcher as a result of the external heart massage.[C3-170] Further exploration during the autopsy disproved that theory. The surgeons determined that the bullet had passed between two large strap muscles and bruised them without leaving any channel, since the bullet merely passed between them.[C3-171] Commander Humes, who believed that a tracheotomy had been performed from his observations at the autopsy, talked by telephone with Dr. Perry early on the morning of November 23, and learned that his assumption was correct and that Dr. Perry had used the missile wound in the neck as the point to make the incision.[C3-172] This confirmed the Bethesda surgeons’ conclusion that the bullet had exited from the front part of the neck.