Mahabharata Anushasna Parva Chapter 85:5

Mahabharata Anushasna Parva (Dana Dharma Parva) Chapter 85:5 "Unto her the deity of fire said, "Do thou bear the seed. Do, indeed, bear the foetus endued with my energy. It will lead to great results. Thou art, verily, capable of bearing the entire earth. Thou wilt gain nothing by not holding this energy. "That foremost of streams, though thus passed by the deity of fire as also by all the other deities, cast off the seed on the breast of Meru, that foremost of all mountains. Capable (somehow) of bearing that seed, yet oppressed by the energy of Rudra (for Agni is identical with Rudra), she failed to hold that seed longer in consequence of its burning energy. After she had cast it off, through sheer distress, that blazing seed having the splendour of fire, O perpetuator of Bhrigu's race, Agni saw her, and asked that foremost of streams, "Is it all right with the foetus thou hast cast off? Of what complexion has it been, O goddess? Of what form does it look? With what energy does it seem to be endued? Do thou tell me all about it." 'Ganga said, "The foetus is endued with the complexion of gold. In energy it is even like thee, O sinless one! Of an excellent complexion, perfectly stainless, and blazing with splendour, it has illuminated the entire mountain. O foremost of all persons endued with penances, the fragrance emitted by it resembles the cool perfume that is scattered by lakes adorned with lotuses and Nyphoea stellata, mixed with that of the Nauclea Cadamba. With the splendour of that foetus everything around it seemed to be transformed into gold even as all things on mountain and low land seem to be transformed into gold by the rays of the Sun. Indeed, the splendour of that foetus, spreading far, falls upon mountains and rivers and springs. Indeed, it seems that the three worlds, with all their mobile and immobile creatures, are being illuminated by it. Even of this kind is thy child, O illustrious bearer of sacrificial libations. Like unto Surya or thy blazing self, in beauty it is even like a second Soma." Having said these words, the goddess disappeared there and then. Pavaka also, of great energy, having accomplished the business of the deities proceeded to the place he liked, O delighter of the Bhrigus. It was in consequence of the result of this act that the Rishis and the deities bestowed the name of Hiranyaretas upon the deity of fire. And because the Earth held that seed (after the goddess Ganga had cast it upon her), she also came to be called by the name of Vasumati. Meanwhile, that foetus, which had sprung from Pavaka and been held for a time by Ganga, having fallen on a forest of reeds, began to grow and at last assumed a wonderful form. The presiding goddess of the constellation Krittika beheld that form resembling the rising sun. She thenceforth began to rear that child as her son with the sustenance of her breast. For this reason, that child of pre-eminent splendour came to be called Kartikeya after her name. And because he grew from seed that fell out of Rudra's body, he came to be called Skanda.