Dinosaurs, with Special Reference to the American Museum Collections

KED DIN

(Ornithischia

in many respects, especially the backward direction of the pubic bone, the presence of a prepubis, in the number of vertebrae co?ssified into a solid sacrum, in the proportions of the ilium and so on. Various features in the anatomy of the head, shoulder-blades and hind limbs are equally suggestive of birds, and it seems probable that the earli

ritosaurus and Corythosaurus of the Middle Cretacic (Belly River); Saurolophus of the late Cretacic (Edmonton); Tra

onverted into efficient grinders by infolding and elongation of the crown of each tooth so as to produce on the wearing surface a complex pattern of enamel ridges with softer dentine or cement intervening, making a series of crests and hollows continually renewed during the wear of the tooth. In the reptile the teeth, originally simple in construction but more numerous and continually renewed as they wear down and

onts: Iguanodo

nithopoda or

truct the true proportions of the animal to which they belonged. With them were found associated the bones of the great carnivorous dinosaur Megalosaurus; and the weird reconstructions of these animals, based by Waterhouse Hawkins upon the imperfect knowledge and erroneous ideas then prevailing, must be familiar to many of the older readers of this handbook. Life size restorations of these and other extinct animals were erected in the grounds of the Crystal Palace at Sydenham, London, and in Cent

ptosaurus, an American r

us strata in which the coal seam lay, and with them were skeletons of other extinct reptiles of smaller size. The open fissure had evidently served as a trap into which these ancient giants had fallen, and either killed by the fall or unable to escape from the pit, their remains had been subsequently covered up by sediments and th

d from the lower jaw and is seen to consist of several close-set rows of numerous small p

ures of the Old World genus. In the National Museum at Washington, are mounted two skeletons of Camptosaurus, a large and a small species, and in the American Museum a skeleton of a small species. It suggests a large

ge in proportions or characters. Its latest member is Thescelosaurus, a contemporary of Triceratops. Part

TNO

are completely consumed. Only in the Iguano