the Tale of Taurus
Zeus transformed himself into a magnificent white bull, and as such he joined King Agenor's grazing herd. Europa noticed the wonderful white beast, who gazed at them all with such a mild manner that they were not frightened.
Europa wove wreathes of flowers for the beast, and wrapped them around his horns. She led him around the meadow, and he was as docile as a lamb. Then, as he trotted down to the seashore, she jumped onto his shoulders. Suddenly, to her surprise and fright, he plunged into the sea and carried the princess to Crete.
As they reached the Cretan shore, Zeus then turned into an eagle and ravaged Europa. She bore three sons, the first of which was Minos."
Source: the Constellations