Mbh 9.36.3b

Beholding that large herd of animals, they began to reflect as to how they two could appropriate that property without giving a share unto Trita. Hear, O king, what those two sinful wretches, Ekata and Dwita, said while conversing with each other! They said, 'Trita is skilled in assisting at sacrifices. Trita is devoted to the Vedas. Trita is capable of earning many other kine. Let us two, therefore, go away, taking the kine with us! Let Trita go whithersoever he chooses, without being in our company!' As they proceeded, night came upon them on the way. They then saw a wolf before them. Not far from that spot was a deep hole on the bank of the Sarasvati. Trita, who was in advance of his brothers, seeing the wolf, ran in fright and fell into that hole. That hole was fathomless and terrible and capable of inspiring all creatures with fear. Then Trita, O king, that best of ascetics, from within that hole, began to utter wails of woe. His two brothers heard his cries. Understanding that he had fallen into a pit, his brothers Ekata and Dwita, moved by fear of the wolf as also by temptation, went on, deserting their brother. Thus deserted by his two brothers, who were moved by the temptation of appropriating those animals, the great ascetic Trita, O king, while within that lonely well covered with dust and herbs and creepers, thought himself plunged, O chief of the Bharatas, into hell itself like a sinful wretch. He feared to die inasmuch as he had not earned the merit of drinking Soma juice. Possessed of great wisdom, he began to reflect with the aid of his intelligence as to how he could succeed in drinking Soma even there. While thinking on that subject, the great ascetic, standing in that pit, beheld a creeper hanging down into it in course of its growth. Although the pit was dry, the sage imagined the existence of water and of sacrificial fires there. Constituting himself the Hotri (in imagination), the great ascetic imagined the creeper he saw to be the Soma plant.