Lorne Campbell think that though the Catherine head is " obviously less well drawn and less successfully painted than the Magdalen " , it " seem likely " that all three fragments came from the same original work ; he point out that " about half way up the right edge of this fragment [ " Catherine " ] is a small triangle of red , outlined by a continuous underdrawn brushstroked ... It is likely that the red is part of the contour of the missing figure of the Baptist " . The small piece is on the outermost edge of the panel , and only visible when it was removed from the frame . Ward believe the piece correspond directly with the folds of John 's robes .