A small herbivorous equid of the genus Hyracotherium (syn. Eohippus ) of the Eocene Epoch, having an arched back, relatively short neck, four-toed front feet, and three-toed hind feet.
A small primitive horse that lived about 50 million years ago during the early Eocene Epoch. It had three or four hoofed toes on each foot and is considered by some to be the ancestor of modern horses. It is sometimes called the “dawn horse,” a translation of its earlier scientific name, Eohippus.