Śatapatha Brāhmaṇa ("of a hundred paths") 2.5.1.2

2.5.1.2

sa aikṣata prajāpatiḥ | yathā nveva puraiko 'bhūvamevamu nvevāpyetarhyeka evāsmīti sa dvitīyāḥ sasṛje tā asya paraiva babhūvustadidaṃ kṣudraṃ sarīsṛpaṃ yadanyatsarpebhyastṛtīyāḥ sasṛja ityāhustā asya paraiva babhūvusta ime sarpā etā ha nveva dvayīryājñavalkya uvāca trayīru tu punarṛcā

Pragâpati thought within himself, 'Even as formerly I was alone, so also am I now alone.' He created a second (race of beings); they also passed away: they are those small crawling reptiles other than snakes. He created a third (race), they say; they also passed away: they are those snakes. Yâgñavalkya, on his part, declared them to be of two kinds only; but of three kinds they are according to the Rik.