Popular Science Monthly/Volume 4/February 1874/The Great Cemetery in Colorado

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IN the composition of his ecclesiastical history, an erudite historian chaptered the narrative into centuries. Perhaps for his subject these divisions were sufficiently generous. Still, as measurements of time they were but puny epochs; and yet they were vast enough for the treatment of that ephemeral worker, man. But He, "who worketh hitherto"—who, as the true Earth's Biographer, wrote on the stony rocks—made his divisions the Ages! Indeed, can those epochs be reduced to years? What a scope must the record of his doings have with whom a thousand years are as a day! Accepting these life-cycles with a significance so grand, we reverently look into this great volume. Its opening chapter is the Cambrian age. But—amazing!—the stony laminæ that make up its leaves are scarcely less than one hundred thousand feet in thickness! It was a time of dreary wildness, and its primeval life-forms were few, and huge rock-masses were tilted up from that sea, and worn down for the bed of the waters. Next came the Silurian age, singing the weird music of its one world-encircling sea. Its forms of life were innumerable. Then flourished the Brachiopods, or shell-bearing worms, and Mollusca, Crustacea, corals, and a few fishes. Then comes the Devonian age. Now it is that what seemed a monotonous, watery waste becomes as a weary Sahara, with many a green-fringed oasis cheered. The late universal sea is dotted with low-lying islands. Very beautiful, though lowly in rank, and not over-luxuriant in numbers, were the plant-forms that fringed those shores. Then the fishes composed the nobility of life. Their patterns were grotesque; and they were clad in mighty plate-armor, massive osseous tiles, of quaintly sculpture. It was an armature that spoke unmistakably of crimson conflicts; for, in sooth, these were not "piping times of peace." Next came the Carboniferous age. The area of land is greatly increased; and it is beautified with a new and amazingly luxuriant vegetation. In this plant régime the queenliest being is the arborescent fern. And this luxuriant vegetation stores up the solar force, a rich legacy for the far-off but "coming man." At this time a few air-breathers occupy the land. "With frog-like affinities, they are of very low reptilian rank.

Passing the Permian and the Jurassic, next comes the Cretaceous age, with the culmination of that reptilian race of monsters of amazing size and most singular aspects. It was, indeed, the companionship of "Beauty and the Beast;" for at this time, also, the nautilus, and the ammonite, those peerless structures of the molluscan life, reveled in beauty and vastness of numbers. But a sad change came, and the gay nautilus tribe was reduced to the merest representation in the animate scale; while the star of the resplendent ammonite went down in utter death. And there must have been peculiar conditions of both land and sea, in that Cretaceous day, or those strange reptiles of Brobdingnagian altitude could not walk on the land; nor could their aquatic congeners of cetacean bulk, the huge sea-reptiles, move in their briny homes; so with the Ammonites, and the great selachian fishes. But these—the beauties and the monsters—all died, for there came in new conditions of the land, the sea, and the air.

And with these new conditions came the Eocene age, or dawn of the Tertiary epoch of Earth's lifetime. So decided was this physical change, that all things were ready for its reception of a new race of living creatures. The very surface was newly and lavishly garnished, like a table awaiting the expected guests. And the atmosphere had a balmier vigor, a sort of climatal ripeness, like the aroma of an autumnal orchard whose fruit has matured. Now came the true grasses, and the grains; and the Rosaceæ plants with the strawberry, blackberry, apple, cherry, and plum, etc. And Nature's guests arrived, and entered upon the enjoyment of an unrestrained existence in her grand domain. And they were welcome guests; for leading the train came the (as yet) noblest of her begettings, beings of true mammalian rank. They were of new forms and new appetencies. Some were petite in size, and some were of more than leviathan proportions, and many were bizarre in form; and all were diverse from every thing that had lived before, or that should ever come after. And so each in its own way, as disposition or convenience prompted, enjoyed life. Some preferred the banks of the great rivers, others the grassy meads of the green valleys, and others the sides of the densely-wooded hills. And the timid rodents hid themselves in their burrows at the roar of the carnivores, while both were startled by the beastly bellowing of the great terrestrial behemoths. And these beings, at least some of them, have left their relics in the far West, in places where, until lately, only the red-man had trod.

The geological age just mentioned is called the Tertiary. It was for the first time with true significance sectioned off by Sir Charles Lyell. This learned geologist noticed that this age opened with animal life more like that of the present than any thing that had been before, and that in respect to the molluscs there were many forms identical with existing shells; and he noticed that, as we ascended in this age, the percentage of forms thus similar very rapidly increased. He, therefore, named the bottom section the Eocene, meaning the dawn; and the middle section the Miocene, meaning less of its dawn, that is, farther on in the day; and the highest section he called the Pliocene, meaning still more advanced. To these has been added another, namely, the Pleistocene.

There are three American names which, in respect to the most recent results in vertebrate paleontology, deservedly stand as its great lights—Prof. Joseph Leidy, Prof. E. D. Cope, and Prof. O. C. Marsh. The last two, with an enthusiasm that has triumphed over great difficulties, have especially produced startling results in their individual explorations of the great graveyards of the ancient dead in our Western Territories. Of the labors of Prof. Cope, as conducted under government auspices, it is proposed here to offer a few results. We shall simply give some details of his work done last summer, as the vertebrate paleontologist in behalf of Prof. F. V. Haydon's "Seventh Annual Report of the United States Geological Survey of the Territories." Prof. Cope found himself literally in a crowded cemetery of a quadrupedal race long extinct.

The list which now immediately follows is limited almost exclusively to the Miocene fossils of "the Bad Lands" of Colorado. It tells a marvelous story of rich and formidable fauna that existed on our virgin continent in that Middle-Tertiary age. The Rodents, or gnawing animals, were well represented. Five genera seem to be established, embracing eighteen species. The predecessors of the squirrels were there. One, named Paramys, was a little larger than our chickaree. One little creature, called Heliscomys, had four teat-like cusps on the crown of each molar in the lower jaw. This was the tiniest thing of them all, and stood, probably, among the Miocene rodents, as the common mouse does among the gnawers of to-day. If, indeed, Heliscomys be the ancestral mouse, our Mus musculus has a very ancient pedigree. The rabbits were represented by the genus Palæologus.

There are eleven species of Insectivora, arranged under five genera, with the names Domnina, Embasis, Miothen, Herpetotherium, and Isacis. Except the last one, all these are allied to the mole. They had doubtless the same burrowing habits and food appetencies as the Talpa tribe that to-day follows and annoys the gardener at his work. It is an item gained of real knowledge as respects animal habits, to learn that the earthworms and the subterranean larval insects were kept in check in the same manner then as now. And, if these are the predecessors of the Talpa race, we would like to know if the primitive stock were as clever engineers at constructing subterranean earthworks, for the mole to-day is a genius in that line. There are six species in the list, and they differ quite a good deal in size; and would seem also to differ in some more important aspects, as the name of the Herpetotherium signifies the "crawling beast." It is worthy of remark that these ancient moles, like the modern, were very small animals. Necessarily, then, the fossil bones must have been very minute. They are, however, preserved with wonderful perfection.

As to that other insect-eater, Isacis, it represented the existing hedgehog, as shown by its anatomical structure. And as snakes abounded then, probably, like its congeners now, it made many a meal of them, utterly regardless even of those poison fangs, if such they had. But the great carnivores had a covetous eye on Isacis, when it probably rolled itself up in its bristling armature, and, in full consciousness of a noli me tangere security, invited its enemy "to kick against the pricks"—in fact, to do his worst. And, doubtless, many a hungry feline, after recklessly accepting the invitation, got very badly worsted. As we shall see, there were little keen-toothed tigers then; but their acquaintance with Isacis always ended in disgust, as futile must have been each effort to get a dinner of hedgehog raw. Similar is the experience of our Adirondack catamounts in their attempts on the Canada porcupine. These fierce cats sometimes perish terribly from inflammation caused by the spines of the porcupine, which they are unable to extract.

The carnivorous animals were largely represented. Prof. Cope gives at least ten species. There are five genera of felines, or cats. One of these is quite small, being only half as large as the domestic species; another one, called Stibarus, for a cat, seems to have been a rather stout animal. Of these felidæ there are three genera which possessed remarkable saw-edged teeth, painfully suggestive of the carcharodont sharks. Accordingly, one of these is named Daptophilus squalidens, which, in plain though somewhat clumsy English, means the "sharklike-devouring lover." We are not from this to think of the grand Mogul, who loved his wives so well that he carved them up; but in metaphysical parlance the phrase must be taken subjectively, as of that absorbing passion where the subject loves to take his victim in—that is to say—one who is as voracious as a shark.

Another of these sabre-toothed tigers had its teeth very strong as well as sharp. "The incisors are very stout, and exhibit slightly curved conic crowns, with a serrulate edge on the inner face." These teeth are more suggestive of the trenchant cutlass than the fine sabre. Though not larger than the existing Canada lynx found in the Adirondack Mountains, this terrible tiger well deserves its fearful name—Machirodus oreodontis—the "mountain-like sword-toothed." Another of these carnivores, a new genus, is called Tomarctus. It had some relationship to the canines, but, if a dog, it was of very large size, as it probably equaled in this respect our native black bear. There were, however, true dogs then; and some of their remains were secured in the expedition. Their bones, associated with those of the rodents and insectivora, are quite numerous. One species, called Lippincott's Canis, was about the size of the coyote, or wolf of the plains. Other species obtained were larger than this; and others again were smaller. A Pliocene mastodon is mentioned, which carries the true Proboscidia far back in time. It is named Mastodon proavus, the specific name meaning "before one's grandfather."

Among these Colorado fossils, the ungulates, or hoofed animals, are very prominent. In the advanced classifications of the mammals, the ungulates are divided into the Perissodactyles, or those ungulates which have an uneven number of toes—as the horse with one toe, and the rhinoceros with three—and the Artiodactyles, or the ungulates with an even number of toes—as the hippopotamus with four toes, and the hog with its two functional toes. Now, of these fossil ungulates it is remarkable that the expedition has brought home from the Miocene twenty Perissodactyles, and the same number of Artiodactyles; and from the Pliocene nine Perissodactyles, of which four are new, and six Artiodactyles, of which three are new; thus making fifty-three ungulates. Of these there are several horses, and all of them, including Anchitherium and Protohippus, have three toes to each foot. These cloven-footed beasts were some of them strange, comprehensive types, possessing in the same individual structural resemblances to both swine and deer; "like the latter, these had no horns; they were about as large as sheep. Others were about the size of gray squirrels, being the smallest of this class of animals ever discovered" (American Naturalist). Indeed, an important paleontological result has been Prof. Cope's determination of the correct relationship of five species (three new, and one new genus, Hypertragulus) to the musk family. The general reader should perhaps be told that the order Ungulata, or hoofed quadrupeds, really absorbs three of the orders in the older classifications, namely, the Pachydermata, the Solidungula, and the Ruminantia. This mentioned, we would say, with no irreverence, that in the Colorado fauna of Tertiary times Nature seemed to indulge, as respects the animals of this order, in the most eccentric extremes of structure, both as to form and size; for some of these hoof-footed ones are scarcely larger than a squirrel, while some are as large as the elephant; and there is a seeming oddity of structure. Though a fact before every one's eyes, yet many are not aware of its existence, viz., that the ox and cow have no teeth in the front part of the upper jaw. When this animal grazes, the tongue makes a curl, or twist, and pulls in the grass, then the lower front teeth are made to meet the firm pad of the front part of the upper jaw, and the grass is then severed. Such is the mode common to the ruminating animals, that is, those which chew the cud. Now, in the natural group Ruminantia, comes a sub-group, the Camelidœ, which includes the camels and the llamas. The dentition of these animals is very aberrant. The upper incisors are not entirely wanting, "there being two canine-like upper incisors, and upper canines as well." In the Pliocene strata of Colorado are found the remains of two species of camels, of enormous size, and which, strange to say, are furnished with complete upper incisors, or front-teeth. These ancient camels, then, did not graze like the ox, but like the horse.

And, among these hoofed creatures, the Rhinocerotidœ are represented by three genera. Two of them belong to the Miocene, and the third, the last discovered, to the Pliocene. This is the new genus Aphelops, a monster of immense proportions. The other two genera are Hyracodon, and Aceratherium. It is remarkable that Prof. Cope has made out seven species of these fossil Rhinocerotidœ, which, until the recent discovery of the living hairy-eared rhinoceros (R. casiotis) at Chittagong, the northern extremity of the Bay of Bengal, was the precise number of the living species known. It amounts to a certainty, then, that our great Western Tertiary was much richer in species, and immensely richer in individuals of these enormous beasts, than is the whole living fauna of the entire world to-day. And what singular relationships did these Rhinocerotidœ hold in those Tertiary times! For there were other animals that held structural alliances with them. One of these the professor has named Basilius, the Miocene King. This the learned man doubtless did in respectful deference to a notable personage that had died some time before. It was in fact in the Eocene reign that this individual flourished. So the professor refers to him as Eobasileus;, while another savant, deep in the lore of those times, contends that it belongs to a different family. That its place is in the new order Dinocerata seems undisputed. What the true dynasty was is not for "the likes of us to say." Besides, we would shudder at any personal attempt to wade this paleontological marsh; and would frankly confess a lack of strength wherewithal to cope with a subject so grave as the one which has grown out of these exhumed remains. But, whatever ground there may be as to specific identity or distinction, on these words of Prof. Cope, in his diagnosis of the genus Eobasileus, there is full accord: It "indicates a remarkable combination of structure not before known to naturalists. The gigantic size of the typical species (E. cornutus) adds to its interest, and shows it to have been the monarch of the remarkable fauna disclosed by recent researches in Wyoming." The genus is "established on remains of five individuals of the average size of the Mastodon Ohioticus.... From the manner of the occurrence of the relics, this animal probably went in families, or herds," as do the existing elephants.

But it is time to return to his Miocene majesty. It was even with Eobasileus much as it has been with other ancient monarchs. He had a wicked way of lifting up his horn. Nay, he lifted them twain; for, owing to an ophthalmic difficulty which seems to have been constitutional—like some modern patriarch, who, when he wants to look upon his household with aspect of authority, doth push his spectacles high up on his head—so this king of the beasts! when he wished to feel,

"I am monarch of all I survey;
My right (who shall dare) to dispute?"—

that is, when he desired to look up and around, like a king, with brow austere—he tossed those spectacular horns on high, and backward. The fact was, his supremacy lay in his horns. And herein were some disadvantages. "Uneasy is the head that wears a crown." Each horn was a magnificent affair. But, as sometimes happens with the leading ornament, it was a little awkward in the setting. It was fixed right over the eye! Still, queer as this was, it had its uses. Hereby was achieved a huge bony arch, or cavern, for the protection of the kingly orb beneath—an important provision in case some sturdy old recalcitrant should stand in the way when his majesty went out on a regulation inspection of the royal domain; for, unlike some of his post-relations in Africa and Asia, who are content to take one horn at a time with their compeers, he never took less than two at a bout. In fact, the Rhinocerotidœ of the Tertiary age had their horns in pairs; and without doubt they were used in many a pell-mell fight—contests that likely had but little thinking as to the method of the conflict. From this arrangement of the horns in pairs on these creatures, so nearly related to the rhinoceros, the professor with a keen sagacity claims to disprove the statement that horns in pairs show relationship to the ruminants. His own words are: "They present no special marks of affinity to the artiodactyles, and show that the paired horns of the Eobasileidœ have no significance in the same direction."

A luminous body, if unobstructed, strews its rays in all directions. And a scientific fact or principle, could our eyes follow the emanations, would be found illuming many if not all other facts in science. It was but lately that the above generalization was reached, when it came forth full-blown from the working out of the new genus Symborodon. Of these very remarkable animals the professor gives us six or seven species. And strange beings, even among their contemporaries, must the Symborodontes have been. There was Symborodon bucco—the last word meaning "the cheeky"—and the fellow had "plenty of cheek." It was certainly so anatomically, and "we" are not speaking metaphorically now. The cheek-bones were enormously developed, so much so that they formed immense osseous masses on each side of his head. Indeed, a blow on the side of his caput would have been simply a capital joke; for how could so unimpressible a skull ever have seen the point? And this same individual comported himself with a ludicrously lofty air, for his eyes were set almost vertically in his head. Perhaps it was the Miocene fashion in the upper ranks to look for something to come down, unlike our Micawber mode of waiting for something to turn up. And this being was nearly as large as an adult elephant. As to what, and how much was his intellectual endowment, we know not. We don't think he was very sharp. But we had forgotten to add this attribute—he had two horns, and they were flat.

Perhaps the Caliban of those strange creatures was Symborodon altirostris; not that he was a dwarf among his compeers, for, though not the largest, he was an individual of great weight in his own day. Nor was it that he had a "forehead villainously low;" but because, on the contrary, he carried a forehead most rascally high, and surmounted by a pair of horns that were murderously straight and sharp. Prof. Cope speaks of this species as the most formidably armed, and as presenting a most outré appearance in life. It can be scarcely doubted that his eminence was held in great consideration by the Symborodon people, and that they gave him a wide berth when he went out to take a constitutional.

Another of these beasts enjoys the name of Symborodon trigonocerus. His horns were three-sided, like a bayonet. To be sure, they were short, and rolled outward, which made them harmless in comparison with the former. This was a large beast, but not so large as Symborodon bucco.

The smallest of these creatures was Symborodon acer. Poor little fellow! How they must have looked down upon him! He was not as big as the Indian rhinoceros. But he had his own revenge for this condition of sub-mediocrity. His horns were very long and round. Indeed, he could boast of this accomplishment. And it was notable that he always kept the fact plainly before his eyes. He had the longest horns of them all, and carried them one on each side of his nasal extremity; and it was generally understood that, when Symborodon acer turned up his nose, he meant mischief.

Speaking of the above group, says Prof. Cope: "Thus it is evident that Symborodon is a true perissodactyle, allied to the Rhinoceridœ." To have discovered and worked out this one group alone should give a man glory enough for one lifetime. And yet we are far from having exhausted the list of ungulates. There are Oreodon, two species; Poëbrotherium, two species; Septomeryx, and many others, all cloven-footed beasts; and about these we have said nothing.

But there is still one mammal to be mentioned; and thereby hangs a tail, for it is a monkey. It is a little fellow, but with a big name you may depend, as witness—Menotherium lemurinum. Unless his name mislead, he was a nimble beast, and, with the lemur instinct, a night-prowler at that; for his anatomy connects him with the Lemurs, the lowest of the monkeys, and, if we mistake not, there were Nasuan relations also,[1] as with those fossil monkeys obtained by Cope, in the Eocene strata in the Bridger beds on Black's Fork, Wyoming.

Thus much for these new mammals, so remarkable in numbers and character. But the reptiles were largely represented also; for there were serpents, lizards, and turtles, found in those Colorado beds. Of the snakes, one, a Neurodromicus, was as large as the black snake; another, a Calamagras, was the size of our water-snake; while another, of the same genus, was about as large as a garter-snake. Of these ophidians, all the species and three of the genera are new to science. One thing is observable in Nature—the provision made for sustaining the proper balance, by keeping in check that which might become in excess. It is plain that the moles were very numerous. But these and their congeners were not relished by the mammalian carnivores. The bad smell of the shrew prevents the cat from eating it. Probably the snakes were less dainty, and herein, perhaps, lay their utility in the animal economy. It might seem that Prof. Cope had assigned to the ophidia a similar task, as he names one species Aphelopis talpivorus, which simply means the mole-eating Aphelopis.

The Lacertilia, or lizards, furnish some interesting traits. Prof. Cope gives six characteristically separated genera, and all are new. Exostinus and Peltosaurus were lizards with bony shields, and symmetrical bony tubercles on the head. Here comes in an interesting fact for science, namely, that this is the first time that the ophidia and lizards have been found in the Miocene strata of America.

The turtles are represented by several species, which, although new, present no features of popular interest.

We will now give some facts pertaining to this work of the Geologists in the Territories.

There were really three expeditions made last summer, one to the "Bad Lands" of Colorado, one to the "Bad Lands" of Wyoming, and the third to the Cretaceous formation of Kansas.

As respects the "Bad Lands" of Colorado: three distinct geological formations were found superimposed, or lying in sequence. First, at the base was a series of strata containing fossil wood. This was Cretaceous, and was known as the "Lignite Division." Next came Strata known as the "White River Division." This was Miocene. The next was the "Loup Fork Division," and this was Pliocene. Of course, speaking geologically, this was top of all.

In the Pliocene the fossils found were twenty-four species, of which ten were new to science. They embraced four carnivora, one proboscidian, a mammoth, seventeen ungulates, of which two were great camels. With these ungulates were a number of Pliocene horses. Two interesting facts were obtained: one, that all the horses had three toes to one foot, and the other that the camels had full sets of incisor teeth in both jaws. In this formation was found the large rhinoceros, Aphelops.

From the Miocene were obtained: rodents, eighteen species; insectivora, eleven; carnivora, ten; perissodactyles, twenty; artiodactyles, twenty—thus making forty ungulates; quadrumana, one; lacertilia, or lizards, seven; ophidia, five; turtles, five. Probably the following may be set down as the chief results growing out of the Miocene harvest: The first is the discovery of monkey remains; the discovery of snakes and lizards in American Miocene, and related to the corresponding genera of the Eocene of Wyoming Territory; the settlement of the correct relations of five species, of which three species and one genus, Hypertragulus, were new, the relation being to Moschidœ, or the musk-deer family; the determination of the genus Symborodon, as allied to the rhinoceros on the one side, and to Eobasileus on the other; the discovery of numerous insectivora, allied to the mole. Such is an epitome of the results of the summer's work in Colorado.

In Wyoming Territory occurred the fact so highly important to strategraphical geology—the discovery of the Bridger strata of fossils just above the coal at Evanston. This fixed the age of the deposit geologically, a fact of primary importance to the geologist; the discovery of the new genus, Anchœnodon, an animal near to the swine animals of the genus Elotherium, also allied to Anthracotherium of Europe; the discovery of the large animal A. insolens; also of long canine tusks of Bathmodon.

In Kansas numerous fishes and reptiles were discovered. One of these was the saurodont (lizard-toothed) fish, Portheus gladius. This creature was terrible. He had a pectoral spine which he could elevate at pleasure, and it was four feet long.

Thus we have for a summer's work, by Prof. Cope, not less than 150 species of vertebrate animals alone, of which 100 are new. This makes no account of the collections of the invertebrates. "There is a view generally entertained by naturalists and geologists, that genera and species of animals and plants are greatly more numerous at the present age of the world than in any previous geological period. This seems to me an entire misconception of the character and diversity of the fossils which have been discovered in the different geological formations." So wrote the lamented Agassiz just twenty years ago. Surely there can be no uncertain opinion on that subject now. "Prof. Cope has obtained from the ancient sea and lake deposits of Kansas, Colorado, Wyoming, Idaho, etc., about 350 species of vertebrated animals, of which he has made known to science for the first time more than 200 species!"

Profoundly and alike wonderful, then, to philosopher and naturalist is this story of the irrevocable extinction of entire races of animals. And the same earth-area of that wellnigh fabulous land has seen even greater things than these; for, both before and since the historic age began, it has beheld the passing away, into the darkest dimness of tradition, whole tribes and languages of men.

  1. Both Profs. Marsh and Cope have collected fossil quadrumana from these great Western graveyards. For a remarkable confirmation thus afforded of a generalization made by the present writer, see article "Coati-Mundi," Popular Science Monthly, December, 1872, page 136, in connection with "Fossil Monkeys," in idem for August, 1873, page 519. It is worthy of remark, also, that recent anatomical studies of the Lemurs, by the younger Milne Edwards, afford additional confirmation.