Lambeosaurus was a crested, duck-billed dinosaur. Its large hollow, bony crest was as big as the rest of its skull. Its function has been much discussed.
Lambeosaurus lived during the later Cretaceous period, about 76 to 75 million years ago (mya). Fossils of it have been found in Alberta (Canada), Montana (USA), and Baja California (Mexico), but only the two Canadian species have been described in detail.
Lambeosaurus was described by Dr. William A. Parks in 1923, 20 years after Lawrence Lambe (an early Canadian fossil hunter) had studied it. The genus ranged over much of North America, and into Mexico.