Śatapatha Brāhmaṇa ("of a hundred paths") 4.5.7.5

4.5.7.5

tadye ete abhitaḥ | pucakāṇḍaṃ śikhaṇḍāsthe ucayāte tayoryaddakṣiṇaṃ tasminnetāścatustriṃśatamājyāhutīrjuhotyetāvānvai sarvo yajño yāvatya etāścatustriṃśadvyāhṛtayo bhavanti tadasyāṃ kṛtsnameva sarvaṃ yajñaṃ dadhātyeṣā hyato gharmam pinvata eṣo tatra prāyaścittiḥ kriyate

And that which is the right one of the two bones with hair-tufts which protrude on both sides of her tail-bone,--thereon he offers those thirty-four oblations of ghee; for as much as are those thirty-four utterances, so much is the sacrifice: thus he lays the whole sacrifice entirely into her; for therefrom she lets the gharma (milk) flow, and this is the atonement therefore.