Mbh 16.4.4

"'Proceeding then to the forest, Keshava beheld Rama sitting in a solitary spot thereof. He also saw that Rama had set himself to Yoga and that from out his mouth was issuing a mighty snake. The colour of that snake was white. Leaving the human body (in which he had dwelt so long), that high-souled naga of a 1,000 heads and having a form as large as that of a mountain, endued besides with red eyes, proceeded along that way which led to the ocean. Ocean himself, and many celestial snakes, and many sacred Rivers were there, for receiving him with honour. There were Karkotaka and Vasuki and Takshaka and Prithusravas and Varuna and Kunjara, and Misri and Sankha and Kumuda and Pundarika, and the high-souled Dhritarashtra, and Hrada and Kratha and Sitikantha of fierce energy, and Chakramanda and Atishanda, and that foremost of Nagas called Durmukha, and Amvarisha, and king Varuna himself, O monarch. Advancing forward and offering him the Arghya and water to wash his feet, and with diverse other rites, they all worshipped the mighty Naga and saluted him by making the usual enquiries.