From Orbis Catholicus:
"Photographs of these objects do not exist. People do not even know what they are, let alone what they are called. They were used until circa 1964 in the papal liturgies. These particular objects were used at the Lateran Archbasilica and only just now were brought to the Vatican's Museo Storico (Historical Museum) for display. The employees do not even know how to describe them. The bird cages represent the Holy Spirit. The wine caskets represent the precious blood while the bread on plate represents the Blessed Eucharist. The bread representation is actually hollow and can be lifted off the plate. They were used, I guess, in the rite of episcopal consecrations."