Maiasaura

Maiasaura was a family of hadrosaurs that lived in North America during the Late Cretaceous Period (about 80 to 75 million years ago). The name 'good mother lizard' refers to the fact that the first conclusive evidence that a mother dinosaur cared for her young was found in this species. Nests, eggs, young in various stages of development, and adults were found together at 'Egg Mountain' in Montana.