IX.This animal might have been a Pig-toothed Mastodon to look at him, but again appearances are deceptive. When we examine his mouth, we find something new and distinctive. The features of novelty have to do of course with his teeth. They are three-ridged; therefore he is a Trilophodon which suggests the very primitive Mastodon, but unlike any other teeth we have examined, the paired cones have grown together to form continuous cross-crests, and in the absence of trefoils and small cones, the valleys between crests are unobstructed. Nothing of the pig about such molars; they are chopping teeth, each lower crest working like a shear-blade on the one above it. These teeth with his short jaw and round, up-curved tusks, mark him the True Mastodon, and yet except for his low forehead, stocky figure and a few other peculiarities, he had the general outward appearance of an ordinary elephant.
The True Mastodon
The True Mastodon was a forest-dweller, and we all know that fossil bones of such animals are extremely rare in ancient deposits. This may account for our lack of knowledge of this race, for there can be no doubt that its process of development consumed a very long period of time. The Long-jawed Trilophodons and Tetralophodons, Beak-jawed and Short-jawed and Pig-toothed Mastodons, all disappeared during or before early Pliocene times. They represent stages and variations of development, but none of them appear to be direct ancestors of the True Mastodon. His earliest known progenitor was the Ancient Mastodon (Palaeomastodon) of the Egyptian Fayum region, and nothing more is known of his family until the middle Miocene of France (Mastodon Tapiroides). Much concerning it remains to be learned in the long intervening period, and such information may be expected to come from northern Africa or southern Asia. His first appearance in North America (Mastodon Merriami) is recorded in certain deposits of Humboldt County, Nevada, alleged to be of middle Miocene age, and his next, (Mastodon Matthewi) in the early Pliocene rocks of snake Creek, Nebraska. The latter's European contemporary (Mastodon Borsoni) was a well known individual who roamed aver Europe as far north as England and eastward to the Black Sea. Although a true Mastodon with cropping teeth, nevertheless this Pliocene animal was an exponent of many ancient ideas with his
low forehead, chin-spout, short-crowned teeth and vestigal lower tusks. No one would have expected such an old-fashioned type to live far into the Pleistocene period and survive more progressive elephants, but this he did and upset learned calculations by living far beyond his time. The Borson Mastodon finally passed away, but he left a descendant who has acquired more fame and recognition than all other mastodons put together. This individual was a chip off the old block (Mammut Americanum) the American Pleistocene Mastodon. Originally he may have lived in northeastern Asia and if so his entry into what is now the United States must have taken place in the northwest, for the Pacific Coast in places was 2000 feet higher than at present and Alaska was connected to northeastern Asia by a broad land-bridge, now represented by a string of islands in the Bering Straits. vHis first appearance in our country is presumed to have occurred in the eastern states, for in Pennsylvania, his remains are very abundant at Port Kennedy Cave near Valley Forge and at Frankstown Cave, associated with great ground-sloths, tapirs, peccaries and other early Pleistocene animals. Newburgh on the Hudson, New York, workmen digging in a bog came upon a complete skeleton, which is now on exhibition in the American Museum of Natural History, New York City. This is known as the "Warren" Mastodon, from Dr. Warren, the original owner of the specimen. The skeleton is that of an adult and in its lower jaw is a vestigal lower tusk about one inch in diameter and eleven inches long. A dozen or more skeletons have been discovered throughout the country but none of them are as complete as the "Warren" specimen. They all show him to be an animal about 9 feet 6 inches tall. This modest height was more than made up for by his great bulk, for he was an extremely massive beast: thick-bodied, broad-hipped, big-boned and huge of limb. He must have been an old-time digger or fighter, for his tusks are as a rule shorter and straighter than those of American mammoths, his contemporaries. His head was much flatter and his jaws longer than any true elephant. The largest tusk known measures 10 feet long and is that of a male. Those of females were much shorter and of less diameter than those of males, and this is true of all elephants and. mastodons too, as far as can be discovered. The American Mastodon was probably covered with hair and underlying wool. In one instance where hair was found near the skeleton, it was quite long, brown in color and of coarse texture. One animal at least fed upon coniferous wood and twigs, as determined by remains found in the body cavity of a New Jersey specimen. It is quite likely that Mastodon diet in general consisted of numerous varieties of succulent vegetation which best suited his teeth. The latter were short-crowned, long-rooted and trilophodont, the crests and valleys being well-defined and without obstructions. The method of tooth-replacement is well illustrated by a collection in the Field Museum of Natural History, Chicago. This consists of ten animals of all ages ranging from calf to adult, all found together in a Post-glacial or comparatively recent mire deposit near Minooka, Illinois, about sixty miles southwest of Chicago [which George, Sr. gave to the Field Museum of Natural History, now the Chicago Museum of Natural History, in 1920 - GL,III, ed.] In this series of jaws, every tooth and every stage of tooth succession is clearly shown, beginning with the first baby premolars. The presence of three and active use of not more than two teeth at one time and the advancement from rear to front in the arc of a circle is well illustrated. Even the rear cavity in each jaw shows its incipient tooth, a mere crown minus roots, with pulp preparing to form the tooth body of dentine beneath.
Most of the True Mastodons found in the Central States are far more modern than those from other localities. The Minooka deposit in a recent one overlying the latest glacial gravel. It was a morass and is now, for modern cattle have not infrequently been mired there. Their bones lie close beneath the surface and below them are numerous skeletons of our well-known bison. The Mastodon remains, a few feet farther down, are piled in heaps, together with bones of Elk, Moose and Virginia deer, and a comparatively unknown individual, the Deer Moose (Cervalces). These associated animals are much less ancient than those from Pennsylvania and the great majority of other localities. In Kentucky, southwest of Cincinnati, remains of over 100 mastodons were found, associated with twenty Columbian Mammoths and mid-Pleistocene mammals. On Lake Erie near Cleveland, bones of Mastodons, Columbian Mammoths and a Giant Beaver (Castoroides) lay in close association. In Shasta County, California, the Mastodon and Columbian Mammoth are found together and with Ground Sloths, Peccaries and Horses. These and many other deposits scattered throughout the country show that the Mastodon lived in America for a very long time; from the days of horses, mammoths, ground-sloths and other early residents to the more modern era of Elk and Virginia Deer. It would seem as though he were about the last prehistoric animal to desert us. His range was the length and breadth of the United States, over which his race wandered to the number of hundreds of thousands. America must have liked the beast as he liked her, otherwise she would not have permitted him to endure so long. Even with their perfected grinding teeth, the Mammoths had died off until only the Mastodon remained. Apparently Nature had become careless in permitting such an old-fashioned type to endure for so long a time, but he was simply a case of inborn adaptibility: the animal's power to make the best of his attainments, although humble they might be. The Post-glacial Epoch probably helped the Mastodon, for it was an ice-melting period, when all low-lying lands were saturated with moisture, a condition favorable to plant development and the growth of soft green food suitable for browsing teeth.
He probably came into contact with the early American "Indian," for there is some slight evidence which bears out this possibility. The Red Man may have had something to do with the beast's extinction, although this is not probable. The real reason for The Mastodon's disappearance is unknown. Possibly it had to do with climatic and topographical changes which adversely affected his habits and food supply. He reached the limit of his attainments, and his path downward led to extinction. He vanished before white men set foot in America, and we were therefore denied intimate acquaintance with one of our grandest native animals, the American Mastodon.
[from the original, typewritten draft with hand-written corrections - GL,III, ed.]