Ovid.
This princess had been promised in marriage to Phineus, her uncle, when Neptune sent a sea-monster to ravage the country, because Cassiope, her mother, had boasted herself fairer than Juno and the Nereides.
"In me the son of thundering Jove behold,
Got in a kindly shower of fruitful gold,
Medusa's snaky head is now my prey,
And through the clouds I boldly wing my way.
If such desert be worthy of esteem,
And, if your daughter I from death redeem.
Shall she be mine? Shall it not then be thought,
A bride, so lovely, was too cheaply bought?