deva-tiryaṅ-narādayaḥ

etat-this (form); nana-multifarious; avataranam-of the incarnations; nidhanam-source; bijam-seed; avyayam-indestructible; yasya-whose; amsa-plenary portion; amsena-part of the plenary portion; srjyante-create; deva-demigods; tiryak-animals; nara-adayah-human beings and others.