http://www.cartage.org.lb/en/themes/sciences/Paleontology/Paleozoology/Mesozoic/1maia6.jpg
Maiasaura Description :
(http://en.wikipedia.org/wiki/Maiasaura)
Maiasaura was large, attaining an adult length of about 9 meters (30 feet) and had the typical hadrosaurid flat beak and a thick nose. It had a small, spiky crest in front of its eyes. The crest may have been used in headbutting contests between males during the breeding season.
This dinosaur was herbivorous. It walked both on two (bipedal) or four (quadrupedal) legs and appeared to have no defense against predators, except, perhaps, its heavy muscular tail and its herd behaviour. These herds were extremely large and could have comprised as many as 10,000 individuals.
