M. Renard advanced the view that Janus and not Jupiter was the original paredra or consort of Juno, on the grounds of their many common features, functions and appearance in myth or rites as is shown by their cross coupled epithets Janus Curiatius and Juno Sororia: Janus shares the epithet of Juno Curitis and Juno the epithet Janus Geminus, as "sororius" means paired, double. Renard's theory has been rejected by G. Capdeville as not being in accord with the level of sovereign gods in Dumézil's trifunctional structure. The theology of Janus would show features typically belonging to the order of the gods of the beginning. In Capdeville's view it is only natural that a god of beginnings and a sovereign mother deity have common features, as all births can be seen as beginnings, Juno is invoked by deliverers, who by custom hold a key, symbol of Janus.