pramukhās tasya cātmajāḥ

svarocisah-Svarocisa; dvitiyah-the second; tu-indeed; manuh-Manu; agneh-of Agni; sutah-the son; abhavat-became; dyumat-Dyumat; susena-Susena; rocismat-Rocismat; pramukhah-beginning with them; tasya-of him (Svarocisa); ca-also; atma-jah-sons.