The word dinosaur was coined by Richard Owen in 1841, deinos (terrible) + sauros (lizard) which describe various extinct reptiles of the orders Saurischia and Ornithischia that flourished during the Mesozoic Era. Dinosaurs were carnivorous or herbivorous, dwelled mostly on land, and varied from the size of a small dog to the largest land animals that ever lived. Anchisaurus is a genus of basal sauropodomorph, and was an early herbivorous dinosaur. Sauropodomorpha ("lizard-footed forms") generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. Shown here is an Anchisaurus skeleton restoration by O.C. Marsh.