; subclass Archosauria, order Ornithischia)
A family of dinosaurs of possibly amphibious habit which averaged about 9 m in body length. Several mummies of hadrosaur dinosaurs have been found, from which it was possible to establish that they were unarmoured and that the digits of the fore limbs were connected by a web of skin. Hadrosaurs flourished in the Late Cretaceous.
Subjects: Zoology and Animal Sciences — Earth Sciences and Geography.