"The contrast between the massive structure of the limb-bones, ribs and tail, and the light construction of the backbone, neck and skull, suggests that the animal was amphibious, living chiefly in shallow water, where it could wade about on the bottom, feeding upon the abundant vegetation of the coastal swamps and marshes, and pretty much out of reach of the powerful and active Carnivorous Dinosaurs which were its principal enemies. The water would buoy up the massive body and prevent its weight from pressing too heavily on the imperfect joints of the limb and foot bones, which were covered during life with thick cartilage, like the joints of whales, sea-lizards and other aquatic animals. If the full weight of the animal came on these imperfect joints the cartilage would yield and the ends of the bones would grind against each other, thus preventing the limb from moving without tearing the joint to pieces. The massive, solid limb and foot bones weighted the limbs while immersed in water, and served the same purpose as the lead in a diver's shoes, enabling the Brontosaurus to walk about firmly and securely under water. On the other hand, the joints of the neck and back are exceptionally broad, well fitting and covered with a much thinner surface of cartilage. The pressure was thus much better distributed over the joint, and the full weight of the part of the animal above water (reduced as it was by the cellular construction of the bones) might be borne on these joints without the cartilage giving way. "Looking at the mounted skeleton we may see that if a line be drawn from the hip joint to the shoulder-blade, all the bones below this are massive, all above (including neck and head) are lightly constructed. This line may be taken to indicate the average water-line, so to speak, of this Leviathan of the Shallows. The long neck would enable the animal, however, to wade to a considerable depth, and it might forage for food either in the branches or the tops of trees, or more probably, among the soft succulent water-plants of the bottom. The row of short spoon-shaped stubby teeth around the front of the mouth would serve to bite or pull off soft leaves and water-plants, but the animal evidently could not masticate its food, and must have swallowed it without chewing as do modern reptiles and birds.