The latter forms, along with Kuni-toko-tachi, one of those pairs of deities, not necessarily male and female, which are common in Japanese mythology. An enumeration of the Gods of the five generations which follow would be tedious and unprofitable. Some of them had probably no existence outside of the imagination of individual writers. They were doubtless invented or collected in order to provide a genealogy for Izanagi and Izanami. With one exception, they have left no trace in myth or in ceremonial. There are no shrines in their honour. Little is to be learnt from their names, the derivation of which is often doubtful. Several of them, however, show that the divinely mysterious process of growth, so all-important to an agricultural nation, had attracted attention.[56] Musubi no Kami (the God of Growth), who forms the sixth generation of deities, is a genuine divinity, of whom more remains to be said hereafter. =Izanagi and Izanami=.--The seventh generation consisted of two deities, Izanagi and Izanami. It is with them that Japanese myth really begins, all that precedes being merely introductory and for the most part of comparatively recent origin. The _Nihongi_ tells us that-- _"Izanagi and Izanami stood on the floating bridge of Heaven, and held counsel together, saying 'Is there not a country beneath?' Thereupon they thrust down the 'Jewel-Spear of Heaven' (Ame no tama-boko) and groping about with it, found the ocean. The brine which dripped from the point of the spear coagulated and formed an island which received the name of Onogoro-jima or the 'Self-Coagulating Island.' The two deities thereupon descended and dwelt there. Accordingly they wished to be united as husband and wife, and to produce countries. So they made Onogoro-jima the pillar of the centre of the land."_ The _Kojiki_ says that Izanagi and Izanami were commanded by all the heavenly deities "to regulate and fully consolidate" the floating land beneath. But all the accounts, the _Kojiki_ included, proceed to represent the islands of Japan as having been generated by them in the ordinary manner. We have therefore three distinct conceptions of creation in Japanese myth--first as generation in the most literal sense, second, as reducing to order, and third, as growth (_Musubi_).[57] The "floating bridge of Heaven" is no doubt the rainbow. It is represented on earth by the _Sori-bashi_ or _Taiko-bashi_ (drum-bridge) a semi-circular bridge over a pond before some Shinto shrines. It has too steep a slope for ordinary use, and is reserved for the Deity and for the priest on solemn occasions, the custom having been in this instance probably suggested by the myth.