NODOSAURUS

extinct genus of Cretaceous armoured dinosaurs of North America (the Cretaceous Period began lasted from 144 to 66.4 million years ago). Nodosaurus, a heavy animal about 6 metres (20 feet) long, had a long tail but a very small head and minuscule brain. For protection against predators, Nodosaurus relied upon a heavy coat of thick bony plates and knobs that covered its back. The front legs were much smaller than the hind legs, and the back was strongly arched.