MUNDUS. - By this term was indicated, in Rome, a small pit, dug in the Palatine, with a vaulted ceiling "in the likeness of the world that lies above us" (Cato, in Festus, 144), into which only one man could descend on the only three days of the year (Aug. 24; Oct. 5; Nov. 8) when it was opened (Mundus patet; cf. Festus, s. v.).
The meaning attributed by the moderns (as already by the ancients) to the m. is twofold. According to the first, this pit, dug according to the Etruscan rite that presided over the founding of cities, was destined to receive the grain selected for the new sowing (a fragment of Festus [126] says ... Cereris qui m. appellatur); in fact it was opened on the eve of the Opiconsivia, the feast of the grain stored in the granaries; at the beginning of October, consecrated to the sowing of spelt; and finally at the time of the sowing of wheat. The second aspect of the m. is connected with the world of the dead. Varro says (in Macrobius, I, 16, 18): "It is as if the door of the gloomy and infernal gods were opened, whenever the m. is opened," whose lower part was consecrated to the Manes gods (Cato, loc. cit.). For which reason, since the m. is like the meeting point between the world of the living and that of the dead, and since it was feared that on the days of opening the souls of the dead would return to earth to spread their harmful action, those three days were called religious, that is, inauspicious for beginning any action, whether public or private (v. also: MORTI, MONDO SOTTERRANEO dei).
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