Parasaurolophus is a genus of ornithopod dinosaur. It is a herbivore that walks both as a biped and a quadruped.
Parasaurolophus is a hadrosaurid, part of a diverse family of Cretaceous dinosaurs known for their range of bizarre head adornments. This genus is known for its large, elaborate cranial crest, which at its largest forms a long curved tube projecting upwards and back from the skull.
Like other hadrosaurids, it is able to walk on either two legs or four. It prefers to forage for food on four legs, but runs on two. The neural spines of the vertebrae are tall, as is common in lambeosaurines tallest over the hips, they increase the height of the back. The most noticeable feature is the cranial crest, which protrudes from the rear of the head and is made up of the premaxilla and nasal bones. The crest is hollow, with distinct tubes leading from each nostril to the end of the crest before reversing direction and heading back down the crest and into the skull.