Vishnupurana 3.2.49

3.2.49

manuḥsaptarṣayo devā bhūpālāś ca manoḥ sutāḥ /
manvantare bhavantyete śakraścaivādhikārimaḥ //

At the end of every four ages there is a disappearance of the Vedas, and it is the province of the seven Rishis to come down upon earth from heaven to give them currency again. In every Krita age the Manu (of the period) is the legislator or author of the body of law, the Smriti: the deities of the different classes receive the sacrifices during the Manwantaras to which they severally belong: and the sons of the Manu them. selves, and their descendants, are the sovereigns of the earth for the whole of the same term. The Manu, the seven Rishis, the gods, the sons of the Manu, who are the kings, and Indra, are the beings who preside over the world during each Manwantara.