A plate of a support structure for a ceiling mold for the production of concrete ceilings, in particular seating plates of a support head with holding means disposed on the plate for a ceiling mold element for gap filling members. A first large protrusion and a second large protrusion are provided in only one corner region of a substantially rectangular plate to hold the ceiling mold element. The first and second large protrusions are wider and higher than a plurality of other smaller protrusions disposed on the upper surface of the plate.