Pherecydes, in his twelfth book, says, that Acrisius married Eurydice, the daughter of Lacedaemon. Danae was the produce of this marriage. Acrisius having consulted the oracle, to know whether he should have a son, the Pythian god answered, that he himself should not have a son; but that his daughter would bear one, who was fated to destroy him. Acrisius, on his return to Argos, caused a brazen chamber to be constructed in the court of his palace; where he shut up Danae with her nurse, and kept her confined and closely watched, to prevent her having a son. Zeus, being enamoured of the virgin, gained admission to her in a shower of gold, which glided through the roof, and was received by Danae in her bosom. The offspring of this intercourse was Perseus. Danae, with the assistance of her nurse, nourished him privately, and eluded the vigilance of Acrisius until he was three or four years old. Then Acrisius, hearing the voice of the infant playing, called Danae and the nurse before him, and killed the latter on the spot. Having led his daughter to the altar of Courtyard Zeus, he interrogated her, without witnesses, respecting the father of the infant. She ascribed him to Zeus; but the father, disbelieving this story, caused a coffer to be made, in which he shut up Danae and her infant, and ordered them to be cast into the sea.
(trans. W. Preston, slightly adapted)
So interesting was the coincidence of a demigod born to a virgin through the intervention of an incorporeal god that Edwin Sidney Hartland argued in his three-volume Legend of Perseus (1894-1896) that the Greek story served as forerunner to the Christian legend, which he sought to reduce to nothing more than one myth among many.
I'll be taking tomorrow off for the holiday, so with that thought, Merry Christmas.