Fig. 22.—Fossil shell of Giant Land Turtle, Testudo orthopygia.
Discovered by Charles Sternberg in Phillips Co., Kansas.
Fig. 23.—The Snake-necked Elasmosaurus, Elasmosaurus platyurus.
Discovered in the Niobrara Group of the Cretaceous. Restoration by Osborn and Knight. (From painting in American Museum of Natural History.)
Not only did I secure a number of specimens of these great turtles, so abundant at this time, but also large quantities of the remains of a rhinoceros. Cope thought it hornless, and named it Aphelops megalodus, but since then Hatcher has found that the male bore a loose horn on the end of the nasal bones.
I also got specimens of the great inferior tusked mastodon, Trilophodon campester Cope. This remarkably primitive mastodon had a lower jaw that projected beyond the molar teeth for two feet in a straight line, with a socket on either side, containing two powerful tusks that terminated in chisel points. One specimen, which I discovered in 1882 for the Museum of Comparative Zoology in Cambridge, had a jaw four feet long, including the tusks, which extended eighteen inches beyond the end of the jaw.
A set of jaws was brought me by my son last fall. It belongs to a new form of this gigantic pachyderm, which, during the Loup Fork times, inhabited northwestern Kansas and a vast territory west and northwest as far as the John Day basin in eastern Oregon. A remarkable peculiarity of this specimen is that the symphysis is greatly elongated and curves downward thirteen inches below the level of the alveolus, which bears the great molar teeth. This individual was an old animal, as he had shed his first dentition and all the premolars and molars of the second except the very last, those which we call wisdom teeth. Even these are well worn; so the days of the mastodon’s life must have been numbered even if he had escaped his enemy, the great saber-toothed tiger, which preyed on him and the other herbivorous animals of the day.
The length of these remarkable jaws is four feet and one inch. The height at the condyle, where they connect with the skull, is thirteen and a half inches; length of molar, nine and a quarter inches; height of crown, two and one-half inches; distance between the two molars, four inches. The sockets for the great inferior tusks are two feet long and six inches in diameter, and the huge recurved tusks themselves must have been over four feet long. Only a sight of these peculiar jaws, with tusks above and below, can give the reader an idea of the formidable appearance of this early mastodon. By the large size and downward curvature of the lower tusks, this mastodon suggests the great Dinotherium of the Lower Pliocene of Europe. I regret for America’s sake, but I am glad for the sake of the world, that these jaws of the largest mammal ever found in Kansas will find their last resting-place in the great British Museum, where many of my finest discoveries have gone.
Another splendid set of lower jaws I found in 1905 in the Sternberg Quarry, of which I shall speak later, for the Royal Museum of Munich, Bavaria. Part of the symphysis was broken off, as were also the inferior tusks. The length of the jaw as preserved is two feet, six inches and a half, and the height of the condyle, fourteen inches. In the center of the grinding surface, the height is nine and a half inches. The length of the molar is about seven and a half inches, and the width three and a half. This is Professor Cope’s Trilophodon.
We found near this mastodon many chisel-like tusks that had fallen out of their respective jaws and lay scattered with the other bones. By comparing this specimen with the new species, it will be noticed that there is quite a difference in size, though evidently they were about the same age, as in both cases all the teeth have been discarded except the last molars.