Edmontonia

Dryosaurus (pronounced /ˌdraɪ.ɵˈsɔrəs/ DRY-o-SAWR-əs; meaning 'oak lizard', due to the vague oak shape of its cheek teeth (Greek δρυο/dryo meaning 'oak' and σαυρος/sauros meaning 'lizard') is a genus of an ornithopod dinosaur that lived in the Late Jurassic period. It was an iguanodont (formerly classified as a hypsilophodont). Fossils have been found in the western United States and Tanzania and were first discovered in the late 19th century. The Tanzanian site proved to be an especially fertile hunting ground for Dryosaurus fossils, this specimen was previously called Dysalotosaurus (meaning "lost wood reptile"). An expedition led by German paleontologist Werner Janensch found a great many fossils that represented Dryosaurus at many stages of development.