The two quatrefoils present us with a puzzle. Between them the lobes of the have eleven characters on each of the left and right quatrefoil, the top, right and left lobes having three characters each whilst the bottom lobes have only two. There is no obvious sign that the left contains only Old Testament characters nor that the right contains only New Testament characters, as is the case in the lower part of the window.
Looking at the left quatrefoil
The top lobe shows three characters, the central character with red robes is holding a chalice containing a serpent which is normally associated with St John the evangelist. There are few clues to the identity of the other two characters.
The left lobe also contains three characters, there are clues to the identity of two of these. The central character in a green robe has what appears to be a red diagonal cross behind him, this is likely to be St Andrew. The character to his left who is half hidden is holding out a collecting box perhaps indicating St Matthew / Levi. There seems little to help identify the third character.
The right hand lobe again has three characters, the foreground figure in a purple robe is holding a paschal lamb but this is open to several interpretations. The figure to his left is holding a sceptre and is possibly female. The third figure is largely obscured.
The bottom lobe only contains two figures which raises the significance of only having eleven figures in each of the two quatrefoils, this idea is repeated in the top layer of the window and will be considered there. The figure to the left with a white robe covering a golden cassock, a white bird is sitting on his kight hand. Like the lamb there is no single obvious candidate from the bird, St David of Wales would be one possibility, if the bird is seen as a dove then Noah would be another and St Francis of Assissi would be a third. The figure to the right is carrying a castle or keep which is again open to multiple interpretations.