Derived from the Latin bulla, “seal,” a bull originally referred to the seal affixed to papal edicts but later was transferred to the edicts themselves. The term is now restricted to the most important papal mandates, which are stamped with an official wax seal. Bulls have been issued to assert major Roman Catholic doctrines. For example, papal supremacy was declared by Pius II in Execrabilis (1460); in Innefabilis (1854) and Pastor Aeternus (1870), Pius IX proclaimed the doctrine of the [[Immaculate Conception]] and papal infallibility. Since 1878 only “consistorial bulls,” signed by the pope and cardinals, are sealed in a special way. The originals of these bulls are kept at Rome and copies are sent out.