Janus owes the epithet "Iunonius" to his function as patron of all kalends, which are also associated with Juno. In Macrobius's explanation: ""Iunonium, as it were, not only does he hold the entry to January, but to all the months: indeed all the kalends are under the jurisdiction of Juno"". At the time when the rising of the new moon was observed by the pontifex minor the rex sacrorum assisted by him offered a sacrifice to Janus in the "Curia Calabra" while the regina sacrorum sacrificed to Juno in the regia.