Period: Late Cretaceous
Order, Suborder, Family: Ornithischia, Ornithopoda, Hadrosauridae
Location: North America (Canada, United States, Mexico)
Length: 30 feet (9 meters)
One species of Lambeosaurus that was common in Alberta had a crest that looked like a hatchet was embedded in the top of its head. The front part of this crest was stout and pointed forward and up from just above the eyes. The crest was hollow and connected to the nostrils. The nasal cavity went down the back of the throat into the lungs. It is this hollow portion of the crest that could produce low frequency sounds for communication between family members or within large herds. The second part of the crest was farther back on its head and solid. This backward projecting "prong" probably supported a frill of skin that went along the back of the animal to the tail. It seems only males had this prong; only half the skulls found had them.
Another species of Lambeosaurus was much rarer. Its crest was very large, flaring forward and upward from the top of the head. The solid prong that extended backward was probably smaller, but it may still have supported a frill of skin down the back of the animal.
The skeleton of Lambeosaurus was robust, with long, sturdy front and back legs. The tail was long and was held straight back when the animal walked. Because of the crests, paleontologists once thought Lambeosaurus and other hadrosaurids lived in water, using their crests as snorkels or for storing air. They may have gone into the water or enjoyed a swim, but all hadrosaurids lived on land.
The name Lambeosaurus, coined in 1923, means "Lambe's reptile" in honor of its discoverer Lawrence Lambe. Lambe described the first specimen of Lambeosaurus as Stephanosaurus in 1914; at that time he did not think it was a new genus. Lambeosaurus was closely related to Corythosaurus and Hypacrosaurus. Some scientists think that a giant 54-foot duckbill specimen found (fragments only) in Baja California may prove to be a species of Lambeosaurus.