He [VálmÃki] was the son of Varuna, the regent of the waters, one of whose names is Prachetas. According to the Adhyátmá Rámáyana, the sage, although a Bráhman by birth, associated with foresters and robbers. Attacking on one occasion the seven Rishis, they expostulated with him successfully, and taught him the mantra of Ráma reversed, or Mará, Mará, in the inaudible repetition of which he remained immovable for thousands of years, so that when the sages returned to the same spot they found him still there, converted into a or ant-hill, by the nests of the termites, whence his name of VálmÃki.
Valmiki