Skandapurana 7.5.36_209

7.5.36_209

daśamādapi cottīrṇaḥ ṣaṭ koṭīrjanmanāṃ32 kṛmiḥ .
śeṣeṇa karmaṇā jātastato bhavati vānaraḥ . . 27..

And emerged even from the tenth, [born as] a worm for six crores of births / through the remainder of his karma, he then becomes a monkey.