King Prithu, son of Vena, makes the Earth yield grain by milking her as a cow; told as a cosmic milking in the Atharvaveda, a friendly one in the Mahabharata and a chase in the Puranas.
Vena bans worship and is killed by the sages; Prithu is produced from his right arm and crowned. His people starve because the plants vanished in the kingless time. He pursues the Earth with his bow; she flees as a cow through the worlds, then argues for her life and offers her milk if he provides a calf and levels the ground. He uproots the mountains, makes Svayambhuva Manu the calf and milks all grains into his hand. Other beings milk her after him. She is named Prithivi as his daughter.
Viraj, who was all this in the beginning and feared by all, rises and goes to each class of beings. The demons call her Maya and milk illusion into an iron pan with Virochana as calf; the ancestors call her Food, with Yama as calf and a silver pail; men call her free-giver: Manu son of Vivasvat is the calf, the Earth is the pail, and Prithi son of Vena milks husbandry and grain. The seven sages, the gods, the Gandharvas, the Other People and the serpents follow, each with calf, milker and pail.
What is different here:
The cow is Viraj, not the Earth; the Earth is only the milking pail. No Vena story, no famine, no chase. Prithi is one milker among many.
In Narada's list of great dead kings: in Prithu's reign the earth bore crops untilled and every lotus held honey. Trees, mountains, gods, demons, men, snakes, sages and ancestors ask him for lasting boons. He takes his bow, thinks, and tells the Earth to yield the milk each wants. She asks to be regarded as his daughter and he agrees. The trees milk first, with the sala as calf and the banyan as milker; men milk crops with Manu as calf and Prithu as milker.
What is different here:
No famine and no flight. The Earth comes when called and asks to be his daughter before the milking, where the Purana makes that an etymology at the end.
Bhishma tells the origin of kingship. Vena, born of Mrityu's daughter Sunitha, is wicked and is killed by the sages with kusha grass. Prithu comes from his right arm, armed and learned, and swears before gods and sages to rule by dharma. He levels the uneven earth with the horn of his bow. The Earth herself comes to his coronation with a tribute of jewels. He draws seventeen kinds of crops from her as from a cow.
What is different here:
A story about the first oath of a king. The Earth attends his crowning as a willing giver; the milking is one sentence.
The chase is told as in the Vishnu Purana, with longer speeches. The Earth, as a cow, praises Prithu as the Lord, then explains that she hid the seeds because they were being consumed by people who did not perform sacrifice and no king was punishing them. She asks for a calf, a pot and a milker and for the ground to be levelled so that rainwater stays on it. Prithu makes Svayambhuva Manu the calf and milks into his cupped hands; a long list of other milkers follows.
What is different here:
Gives the Earth a stated reason for withholding the seeds and a hymn of praise to Prithu as Vishnu; adds the practical point about holding rainwater.
Sources: The Vishnu Purana, tr. H. H. Wilson (1840); Hymns of the Atharva-Veda, tr. R. T. H. Griffith (1895); The Mahabharata, tr. K. M. Ganguli (1883-96), sections read for the Vedic layer; Srimad-Bhagavatam (Bhaktivedanta Vedabase)