"The feline Sphinx roamed free as air"

In Greek mythology, the Sphinx is a creature with the head of a woman, the body of a lioness, the wings of an eagle, and a serpent-headed tail. The Sphinx guarded the gateway to the city of Thebes, and asked all who would enter a riddle, that they must solve in order to pass. The riddle was: "Which creature in the morning goes on four legs, at mid-day on two, and in the evening upon three, and the more legs it has, the weaker it be?" The answer is 'Man', referring to the ages of man as baby, adult and elder. Oedipus was able to solve the riddle, and the Sphinx, angered, killed herself.