Origin of the Shield Shape in the Solar Folio of the f85-86 Foldout

[Dobri]

The bench has to be a ligature. 
The ligatures of the gallows have to be nested between the two symbols of the bench ligature. 
Another less plausible option is that the gallows ligatures are suprascript to be pronounced after the bench but there are examples of gallows written after the bench for this case.