The outer face is carved with the head of a 'green man'. The style is vigorous, with two strands of foliage emerging from the corners of a grimacing mouth. These strands expand to form exuberant and well-modelled leaves which surround the head. The fragment of vault rib which remains is moulded with a broad axial filleted roll flanked on each side by a hollow and part of a small half-roll. The rest of the rib is hidden by the wall in which the vault boss is set.