
Euoplocephalus was a large armored dinosaur, measuring about 20 feet (6 m) long; it weighed about 2 tons. Its wide head had a horny, toothless beak, small, peg-like cheek teeth, bony horns, and a small brain.

Parasaurolophus grew to be about 40 ft (12 m) long and 8 feet (2.8 m) tall at the hips. It weighed about 2 tons. It had pebbly-textured skin, a spoon-shaped beak, and a pointy tail. It may have had webbed fingers, giving it a mitten-like hand, but some paleontologists argue that the web-like fossilized hands are an artifact of the fossilization process. Its sight and hearing were keen, but it had no natural defenses. It had a toothless, horny beak and numerous cheek teeth.

Ornithomimus was an omnivore, eating both plant and animal matter, including insects, small reptiles and mammals, eggs, fruit, and leaves.