 Corythosaurus / ˌkɒrᵻθoʊˈsɔːrəs / is a genus of hadrosaurid " duck @-@ billed " dinosaur from the Upper Cretaceous Period , about 77 – 75 @.@ 7 million years ago . It lived in what is now North America . Its name means " helmet lizard " , derived from Greek κόρυς . It was named and described in 1914 by Barnum Brown . Corythosaurus is now thought to be a lambeosaurine , related to Nipponosaurus , Velafrons , Hypacrosaurus , and Olorotitan . Corythosaurus has an estimated length of 9 metres ( 30 ft ) , and has a skull , including the crest , that is 70 @.@ 8 centimetres ( 27 @.@ 9 in ) tall . 
 Corythosaurus / ˌkɒrᵻθoʊˈsɔːrəs / <a href='drop_aux' title='1'><mark>is</mark></a>a genus of hadrosaurid " duck @-@ billed " dinosaur from the Upper Cretaceous Period , about 77 – 75 @.@ 7 million years ago . It lived in what is now North America . Its name <a href='uninflect' title='2'><mark>means</mark></a> " helmet lizard " , derived from Greek κόρυς . It was named and described in 1914 by Barnum Brown . Corythosaurus is now thought to be a lambeosaurine , related to Nipponosaurus , Velafrons , Hypacrosaurus , and Olorotitan . Corythosaurus <a href='got' title='3'><mark>has</mark></a> an estimated length of 9 metres ( 30 ft ) , and <a href='got' title='4'><mark>has</mark></a> a skull , including the crest , <a href='null_relcl' title='5'><mark>that</mark></a>is 70 @.@ 8 centimetres ( 27 @.@ 9 in ) tall . 
Corythosaurus / ˌkɒrᵻθoʊˈsɔːrəs / a genus of hadrosaurid " duck @-@ billed " dinosaur from the Upper Cretaceous Period , about 77 – 75 @.@ 7 million yrs ago . It lived in what is now North America . Its name mean " helmet lizard " , derived from Greek κόρυς . It was named and described in 1914 by Barnum Brown . Corythosaurus is now thought to be a lambeosaurine , related to Nipponosaurus , Velafrons , Hypacrosaurus , and Olorotitan . Corythosaurus got an estimated length of 9 metres ( 30 ft ) , and got a skull , including the crest , is 70 @.@ 8 centimetres ( 27 @.@ 9 in ) tall .