Hyracotherium or Eohippus, extinct genus of perissodactyl ungulates that lived during the Tertiary to Eocene Epoch

Hyracotherium or Eohippus, the dawn horse, extinct genus of perissodactyl ungulates that lived during the Tertiary to Eocene Epoch. Colour printed (chromolithograph) illustration by Heinrich Harder from 'Tiere der Urwelt' Animals of the Prehistoric World, 1916, Hamburg. Heinrich Harder (1858-1935) was a German landscape artist and book illustrator. From a series of prehistoric creature cards published by the Reichardt Cocoa company. Natural historian Wilhelm Bolsche wrote the descriptive text. (Photo by: Florilegius/Universal Images Group via Getty Images)