Fig. 13.—a, Lower Jaw of Trachodon marginatus, SHOWING SUCCESSIVE LAYERS OF TEETH. b, Top and side views of a tooth of Myledaphus bipartitus.
(After Osborn and Lambe.)
Fig. 14.—Skull of a Duck-billed Dinosaur, Diclonius, FOUR FEET IN LENGTH. (In American Museum of Natural History.) Photo, by Matthew.
We found no complete specimens of any fossil animals during our stay on Dog Creek, but near the summit of the Bad Lands, under beds of yellowish sandstone, we came upon localities literally filled with the scattered bones and teeth of dinosaurs, those terrible lizards whose tread once shook the earth. They are represented now by the little horned toad of central Kansas. Among the fragments were pieces of the finely-sculptured shells of the sea turtles, Trionyx and Adocus, and remains of that strange dinosaur Trachodon (Fig. [13]a), whose teeth were arranged as in a magazine, one below another, so that when the old teeth wore out, others were ever ready to take their place.
The specimen in the illustration is from Drs. Osborn and Lambe’s Contribution to Canadian Paleontology, on the Vertebrata of the Mid-Cretaceous of the Northwest Territory (1902). The splendid Cretaceous dinosaur here illustrated is from Wyoming (Fig. [14]). This last form was restored by the late Professor Marsh, and is now mounted in the museum of Yale University. What a strange picture it presents, this great plant-eater, as, standing on its hind limbs, its powerful tail acting as the third leg of a tripod, it grasps the branches of a tree with its weak hands and arms, while its teeth scrape off the tender leaves!
In one of these localities we found teeth belonging to some extinct ray-like fish that were arranged in the roof and floor of the mouth like bricks in a pavement, forming a sort of mill which ground up the shells upon which the creature subsisted. A strange thing about these teeth was that one side of the enamel was white and the other black. Cope called the species Myledaphus bipartitus (Fig. [13]b).
The diamond-shaped enameled scales of the Lepidotus, an ancient relative of the gar-pike, were very common, as were also the teeth of several species of dinosaurs besides those already mentioned.
To-day the great museums of the country have complete or nearly complete skeletons of these creatures, the largest land animals that ever inhabited the earth. The splendid specimen of Brontosaurus (Fig. [16]) in the American Museum at New York is over sixty feet long. Nothing so fires the imagination as a visit to the halls where these ancient lizards now stand.
I am delighted that recent authorities, Drs. Osborn and Lambe, have given Professor Cope credit for these discoveries of his in 1876, discoveries which are made the more memorable by the fact that he was the first scientist who had the foresight and the courage to explore these fossil beds after Dr. Hayden, their original discoverer, was driven out of the region by Blackfeet Indians. Indeed, the chief purpose of this chapter is to put forward the claim that Professor Cope, Mr. Isaac, and myself made the first real collection of these wonderful saurians.