“…The origin and course of coronary vessels: embryological considerations I HAVE READ WITH GREAT INTEREST THE REPORT of Ho et al 1 on an unusual course of a coronary artery arising from the pulmonary trunk. This is interesting not only because of the fascinating course of the distal main stem of the anomalous artery through the musculature of the left atrial wall, but especially because of its free course across the pericardial cavity.…”