It is now accepted that there were different types of Iguanodontids ie dinosaurs with teeth that look like those of the Iguana. This early plant eating creature whose remains had been found around the south of England was identified as Iguanodon and first publicised by Mantell in a letter to Davies Gilbert who read it to the Royal Society of London on 10 Feb 1825 entitled “Notice on the Iguanodon, a newly discovered fossil reptile from the sandstone of Tilgate Forest” This made Iguanodon the second land dinosaur to be named (after Megalosaurus).
It has been assumed that there were two species of Iguanodon – a larger form called Iguanodon bernissartensis, from remains found in a coal mine in Belgium, and a more graceful species called Iguanodon atherfieldensis, more common in southern England. Although there may have been other sub species as they lived from the late Jurassic through to the late Cretaceous. This latter has now been renamed Mantellisaurus atherfieldensis after Mantell.
This model of the mantellisaurus drinking is for sale from https://www.everythingdinosaur.com/
See here for the background story of the discovery of these dinosaurs http://www.dinosaurisle.com/iguanodon.aspx