Śatapatha Brāhmaṇa ("of a hundred paths") 2.6.2.10

2.6.2.10

atha ya eṣa eko 'tirikto bhavati | tamākhūtkara upakiratyeṣa te rudra bhāga ākhuste paśuriti tadasmā ākhumeva paśūnāmanudiśati teno itarānpaśūnna hinasti tadyadupakirati tira iva vai garbhāstira ivaitadyadupakīrṇaṃ tasmādvā upakirati tadyā evāsya prajā ajātāstā rudriyātpramuñcati

Now as to that additional (cake),--he buries it in a mole-hill, with the text (Vâg. S. III, 57 b), 'This is thy share, O Rudra! the mole is thy animal (victim).' He thus assigns to him the mole as the only animal, and he (Rudra) does not therefore injure any other animal. Then as to why he buries (the cake): concealed, indeed, are embryos, and concealed also is what is buried,--that is why he buries it. By this (offering) he delivers from the power of Rudra those descendants of his, that are not yet born.