A surname of Janus as the opener of the sky, the clouds, the land and the sea. In times of war the doors of the temple of Janus Patulcius were open. The temple was thrice closed on this account: in the time of Numa, after the first Punic war, and after the battle of Actium. The epithet was also applied to Jupiter and Juno. Cp. Clusius, Geminus.
- Macrobius. Saturnalia i, 9.15 ff.
- Ovid. Fasti i, 129, 282.