
Psittacosaurus
Psittacosaurus (meaning “parrot lizard”) was a small, very primitive ceratopsian. This fast-moving plant-eater had a narrow, horny beak with no teeth, and cheek teeth towards the rear of the mouth. It had a boxy skull with short, horn-like projections on the cheeks. It had four long fingers on each hand; the arms were much shorter than the legs.