The portion of a lower jaw in the Oxford Museum is twelve inches long, with a row of nine teeth, or sockets for teeth. The structure of the teeth leaves no doubt as to the carnivorous habits of the creature. With a length of perhaps thirty feet, capable of free and rapid movement on land, with strong hind limbs, short head, with long pointed teeth, and formidable claws to its feet, the Megalosaur must have been without a rival among the carnivorous reptiles on this side of the world. It probably walked for the most part on its hind legs, as depicted in our illustration, and Professors Huxley and Owen, on examining the bones in the Oxford Museum, were much impressed with the bird-like character of some parts of the skeleton, showing an approach to the ostrich type. The form of the teeth, as pointed out by Dr. Buckland, exhibits a remarkable combination of contrivances. When young and first protruding above the gum, the apex of the tooth presented a double cutting edge of serrated enamel; but as it advanced in growth its direction was turned backwards in the form of a pruning knife, and the enamelled sawing edge was continued downwards to the base of the inner and cutting side, but became thicker on the other side, obtaining additional strength when it was no longer needed as a cutting instrument (Fig. 12). [Illustration: Fig. 12.--Lower jaw-bone of Megalosaurus, with teeth.] The genus Megalosaurus--now rendered classic through the labours of Professors Buckland, Phillips, and Owen--may be regarded as the type of the carnivorous Dinosaurs; and it affords an excellent and instructive instance of the gradual restoration of the skeleton of a new monster from more or less fragmentary remains. Certain very excusable errors were at first made in the restoration, but these have since been rectified by a comparison with the allied American forms, such as Allosaurus, of which nearly entire skeletons have of late been discovered in strata of Jurassic age--in fact, the same rock in Colorado as that in which the huge Atlantosaurus bones lay hid. The accompanying woodcut (Fig. 13) shows how the skeleton has been restored in the light of these later discoveries of Professor Marsh. The large bones of the limbs of these formidable flesh-eating monsters were hollow, and many of the vertebræ, as well as some of those of the feet, contained cavities, or were otherwise lightened in order to give the creature a greater power of rapid movement. [Illustration: Fig. 13.--Skeleton of Megalosaurus, restored. (After Meyer.)]