 Benson et al . ( 2012 ) estimated that Corythosaurus has an average length of 9 metres ( 30 ft ) . Richard <unk> Lull 's earlier length estimate , published in 1942 , found a slightly longer total length of 9 @.@ 4 m ( 31 ft ) , a size similar to Lambeosaurus lambei , another Canadian lambeosaurine . In 1962 , Edwin H. <unk> used models of specific dinosaurs , including Corythosaurus , to estimate their weight . The Corythosaurus model used , was modelled by Vincent <unk> after a mounted skeleton , and supervised by Barnum Brown . After testing , it was concluded that the average weight of Corythosaurus was 3 @.@ 82 tonnes ( 3 @.@ 76 long tons ; 4 @.@ 21 short tons ) . More recent size estimates of Corythosaurus , published in 2001 , find the genus to be among the largest hadrosaurids , only smaller than <unk> and Parasaurolophus . The total length of Corythosaurus specimen AMNH 5240 was found to be 8 @.@ 1 m ( 27 ft ) , with a weight of 3 @.@ <unk> tonnes ( 3 @.@ <unk> long tons ; 3 @.@ <unk> short tons ) . 
