Śatapatha Brāhmaṇa ("of a hundred paths") 1.3.2.8

1.3.2.8

sa yaccaturjuhvāṃ gṛhṇāti | ṛtubhyastadgṛhṇāti prayājebhyo hi tadgṛhṇātyṛtavo hi prayājāstattadanādiśyājyasyaiva rūpeṇa gṛhṇātyajāmitāyai jāmi ha kuryādyadvasantāya tvā grīṣmāya tveti gṛhṇīyāttasmādanādiśyājyasyaiva rūpeṇa gṛhṇāti

Now when he takes of it four times (with the sruva) in the guhû, he takes it for the seasons, since he takes it for the fore-offerings, and the fore-offerings are the seasons: all this he takes in the form of butter without making any announcement, in order to avoid sameness; for if he were to take it with the formulas 'For Spring (I take) thee!' 'For Summer--thee!' he would commit (the fault of) a repetition: he therefore takes it in the form of butter without making any announcement.