During the time of Svāyambhuva Manu, these sons all became the demigods collectively named the Tuṣitas. Marīci became the head of the seven ṛṣis, and Yajña became the king of the demigods, Indra.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
तुषिता नाम ते देवा आसन् स्वायम्भुवान्तरे । मरीचिमिश्रा ऋषयो यज्ञः सुरगणेश्वरः
tuṣitā nāma te devā āsan svāyambhuvāntare | marīcimiśrā ṛṣayo yajñaḥ suragaṇeśvaraḥ
SB 4.1.8