Pachycephalosauria

Pachycephalosauria is a clade of ornithischian dinosaurs. Most lived during the Late Cretaceous Period, in what is now North America and Asia. They were all bipedal, herbivorous/omnivorous animals with thick skulls. While traditionally regarded as distinct species or even families, the flat-headed pachycephalosaurs may actually represent juveniles of dome-headed adults. For more information, visit the Wikipedia entry. Get back to Dinosauria
Dracorex	Pachycephalosaurus	Prenocephale	Stygimoloch