Warde Fowler speculates its original function as a storehouse (penna) for the best of the harvest, to provide seed-grain for the next planting, becoming a largely symbolic penna of the Roman state.
quelle: http://en.wikipedia.org/wiki/Ceres_(mythology)
Georges weiß nichts von einer solchen Bedeutung.
http://www.zeno.org/Georges-1913/A/penna?hl=penna