Śatapatha Brāhmaṇa ("of a hundred paths") 13.4.3.9

13.4.3.9

atha pañcame'han evamevaitāsviṣṭiṣu saṃsthitāsveṣaivāvṛdadhvaryaviti havai hotarityevādhvaryurarbudaḥ kādraveyo rājetyāha tasya sarpā viśasta ima āsata iti sarpāśca sarvavidaścopasametā bhavanti tānupadiśati sarpavidyā vedaḥ so'yamiti sarpavidyāyā ekam parva vyācakṣāṇa ivānudra>

And on the fifth day, after those (three) offerings have been performed in the same way, there is the same course of procedure. 'Adhvaryu!' he (the Hotri) says.--'Havai hotar!' replies the Adhvaryu.--'King Arbuda Kâdraveya,' he says; 'his people are the Snakes, and they are staying here;'--both snakes and snake-charmers have come thither: it is these he instructs--'The Sarpavidyâ (science of snakes) is the Veda: this it is;' thus saying, let him go over one section of the Sarpavidyâ as if reciting it. The Adhvaryu calls in the same way (on the masters of lute-players), but does not perform the Prakrama oblations.