1. Triassic Period Jurassic Period Cretaceous Period Dinosaurs of North America

2. * Anchisaurus Anchisaurus Lived in eastern USA * Massospondylys Massospondylys Lived in Arizona * Coelophysis Coelophysis Lived in western USA * Dilophosaurs Dilophosaurs Lived in Arizona 248 to 206 Million Years Ago

3. * Stegosaurs Stegosaurs Lived in western USA * Diplodocus Diplodocus Lived in western USA * Allosaurus Allosaurus Lived in western USA * Torvosaurus Torvosaurus Lived in Colorado and Wyoming 206-145 Million Years Ago

4. * Iguandon Iguandon Lived in western USA * Ankylosaurus Ankylosaurus Lived in western North America * Troodon Troodon Lived in western North America * Tyrannosaurus Rex Tyrannosaurus Rex Lived in western North America 144 to 65 Million Years Ago