Diplodocus is a genus of extinct diplodocid sauropod dinosaur of the Late Jurassic period. Colour printed 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.