Stefan Weinstock conjectured that these three doorway deities had a place in cosmology as the "Ianitores terrestres", "doorkeepers of the earth," guarding the passage to the earthly sphere. In the schema presented by Martianus Capella, the "Ianitores terrestres" are placed in region 16 among deities of the lowest ranks, while Janus, the divine doorkeeper "par excellence", is placed in region 1. This arrangement may represent the "ianuae coeli", the two doors of the heavens identified with the solstices. Isidore of Seville says that there are two "ianuae coeli", one rising (that is, in the East) and one setting (the West): "The sun advances from the one gate, by the other he recedes."