Dinosaur Pachycephalosaurus/Tylosteus is a genus of pachycephalosaurid dinosaurs. It lived during the late Cretaceous in what is now North America. Remains have been excavated in Montana. It was an herbivorous creature which is only known from a single skull and a few extremely thick skull roof.
Pachycephalosaurus was probably bipedal and was the largest known of the bone-headed dinosaurs, with some others being Stygimoloch, Dracorex, and Stegoceras. It is famous for having a large, bony dome atop its skull, up to 25 cm (10 inches) thick, which safely cushioned its brain. The dome's rear aspect was edged with bony knobs and short bony spikes were projected upwards from the snout.
Using data from other pachycephalosauridae, it has been estimated that Pachycephalosaurus was approximately the length of a large car, maybe around 4.6m long (15 feet) and had a fairly short, thick neck, short forelimbs, a bulky body, long hind legs and a heavy tail, which was likely to have been held rigid by ossified tendons. Large eye-sockets that faced forward suggest that the animal had good vision and was capable of binocular vision. All these Dinosaur Pachycephalosaurus pictures were collected from the internet. Enjoy!