Śatapatha Brāhmaṇa ("of a hundred paths") 11.5.2.2

11.5.2.2

sa vai varṣiṣṭhaḥ puroḍāśo bhavati tasmādiyamāsāṃ varṣiṣṭhedaṃ sārasvatamidam pauṣṇamatha ya eṣa upariṣṭāddhastasya saṃdhistanmārutamidaṃ vaiśvadevaṃ dordyāvāpṛthivīyaṃ tadvā aniruktam bhavati tasmāttadaniruktam

That cake (to Savitri), doubtless, is the largest, and hence this (middle finger) is the largest of these (fingers). That (oblation) to Sarasvatî is this (third) finger; and that to Pûshan this (little finger). And that (oblation) to the Maruts is this joint above the hand (the wrist); and that to the Visve Devâh is this (elbow); and that to Heaven and Earth is this arm: this (oblation) is indistinct, whence that limb also is indistinct.