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Conclusions regarding the divisions of the Pleistocene 1-15 Limits of the Pleistocene 1 The Blanco Pliocene 1 Divisions of the Pleistocene 2 Elevation of Continent 3 Connections of North America with South America and Asia 3 Sources of vertebrates 4 Richness of Pleistocene life 4 Evolution during the Pleistocene 5 Extinction of species 6 The earliest Pleistocene, the Nebraskan 7 The Aftonian interglacial 10 The Yarmouth interglacial 12 The Illinois glacial 12 The Sangamon interglacial 12 The Peorian interglacial 13 The Wisconsin and the Wabash beds 13 Coastal Plain terraces 13

Conspectus of Geology and Vertebrate Palaeontology of the Pleistocene 14-15

Finds of Pleistocene cetaceans in eastern North America 17-20 Ontario 17 Quebec 18 Vermont 19 New Brunswick 19 North Carolina 20 South Carolina 20 Florida 20

Finds of mastodons in eastern North America 45-128 Ontario 45 Cape Breton Island 46 Massachusetts 47 Connecticut 47 New York 48 New Jersey 63 Pennsylvania 68 Ohio 70 Michigan 80 Indiana 88 Illinois 100 Wisconsin 110 Maryland 112 Virginia 113 West Virginia 115 North Carolina 115 South Carolina 118 Georgia 120 Florida 121 Alabama 124 Mississippi 124 Tennessee 127 Kentucky 128

Finds of tapirs in eastern North America 203-210 Pennsylvania 203 Ohio 203 Indiana 203 Maryland 204 Virginia 204 South Carolina 204 Georgia 206 Florida 206 Mississippi 208 Tennessee 209 Kentucky 209 Rhinoceroses in Florida 211

Finds of peccaries in eastern North America 212-223 New York 212 New Jersey 213 Pennsylvania 213 Ohio 214 Michigan 215 Indiana 216 Illinois 218 Wisconsin 219 Maryland 220 Virginia 221 West Virginia 221 South Carolina 221 Florida 222 Tennessee 222 Kentucky 223

Finds of camels in eastern North America 224-225 Pennsylvania 224 Florida 224 Tennessee 225

Finds of musk-oxen in eastern North America 248-255 Grinnell Land 248 New Jersey 248 Pennsylvania 248 Ohio 249 Michigan 250 Indiana 251 Illinois 253 West Virginia 254 Mississippi 254 Kentucky 255

Finds of extinct bisons in eastern North America 256-265 Ontario 256 Pennsylvania 256 Ohio 257 Indiana 257 Illinois 259 Wisconsin 259 Maryland 259 Virginia 259 South Carolina 260 Georgia 261 Florida 262 Alabama 264 Mississippi 264 Kentucky 265

Pleistocene Geology of eastern North America and its fossil vertebrates 281-406 Ontario 281 Quebec 288 New Brunswick, Nova Scotia, Cape Breton Island 289 New England 290 New York 294 New Jersey 299 Pennsylvania 306 Ohio 324 Michigan 330 Indiana 331 Illinois 334 Wisconsin 340 Maryland and District of Columbia 344 Virginia 351 West Virginia 354 North Carolina 355 South Carolina 361 Georgia 368 Florida 372 Alabama 384 Mississippi 385 Tennessee 393 Kentucky 400

PLATES.

TEXT-FIGURES.

PREFACE.

The writer has been engaged for several years on an investigation of the Pleistocene geology of North America and of the Vertebrata which have been discovered in the deposits of this epoch. It had been his expectation to publish the results of all his studies at the same date. However, on consultation with Dr. John C. Merriam, it was agreed that it would be better to publish immediately that part which pertains to the region lying east of the Mississippi River and, as to the country further north, that east of longitude 95?.

At the outset the writer was convinced that, before just conclusions could be reached, it was necessary to know what fossil materials had been collected and under what geological and geographical conditions. He therefore made as thorough a search as possible of the literature for reports of discoveries of fossil vertebrates. Also, when in scientific journals or in newspapers the finding of fossils was recorded, recourse was had to correspondence, thus securing much exact information as to locality, kind of matrix, depth, and other important data. Often photographs have been obtained and even the materials themselves. The writer has also visited many museums and colleges throughout the country and examined their collections. Even in the smaller institutions, where perhaps only a few objects have been secured and preserved, some of these have furnished important information. Regret may be expressed that in the larger museums and colleges, as well as the smaller ones, too often there have been preserved only meager or no records regarding the history of what would otherwise be valuable specimens.

In order to show the geographical distribution of the most important species that occur in considerable numbers, a series of maps has been prepared, pertaining to the following:

Whales and porpoises. Seals and walruses. The edentates. Elephas primigenius. E. columbi. E. imperator. E. species undetermined. Mastodons, mostly Mammut. Horses, mostly Equus. Tapirs. Peccaries. Camels. Odocoileus. Cervus. Rangifer. Musk-oxen. Bisons, extinct. Bison bison. Giant beavers.

Other maps and figures for illustration of the Pleistocene geology will be found in their proper places.

The first part of the present volume is occupied by a consideration of the specimens recorded on the maps. Such information is noted as could be secured, often satisfactory, little enough sometimes; but it has been found that one can not foresee what important information a given fossil may furnish. At least, the presence of the fossil at a locality indicates the existence there of Pleistocene deposits of some kind. In cases where other species have been associated with the one mapped and described, these are noted.

When the consideration of these mapped species and genera is completed, the Pleistocene geology of the various States and provinces is taken up, so far as it is related to the vertebrate palaeontology. This involved an examination of much of the literature of the Glacial period; and here one soon finds himself in face of huge tomes and endless articles and detailed maps. Only somewhat less in amount is the literature of the States beyond the glaciated area. The opportunity to misunderstand and to commit errors is unlimited, and the writer can only hope for lenient criticism.

An attempt has been made in the case of all vertebrate fossils to determine their geological relations and to derive some general conclusions regarding the history of our Pleistocene vertebrates and their relation to the divisions of the Pleistocene epoch. The conclusions reached are embodied in the immediately succeeding pages.

Not much attention has been given to the fossil invertebrates and plants. It is evident that neither the mollusks nor the plants have undergone any considerable change during Pleistocene times and are therefore not available as indicators of geological stages, though often useful for determining local climatic conditions. Their value can be better utilized by the palaeomalacologists and palaeobotanists.

To the officers of museums and colleges and to the private individuals who have so freely offered the use of their materials and in other ways aided the writer, he takes pleasure in expressing his sincere thanks. Most of all, however, he is indebted to the Carnegie Institution of Washington for the generous support extended during the years of this investigation.

JUNE 1, 1922.

OLIVER P. HAY.

THE PLEISTOCENE OF NORTH AMERICA AND ITS VERTEBRATED ANIMALS.

CONCLUSIONS REGARDING THE DIVISIONS OF THE PLEISTOCENE.

The Pleistocene is regarded as being equivalent to what is known as the Glacial period. It began with the deployment of the ice-sheets which, proceeding from their centers of accumulation in British America, laid down in the East the Jerseyan drift and in the West the Nebraskan. The more the Glacial period is studied the more one becomes impressed with the significance of its physical effects on the northern hemisphere and with its influence on the vertebrate life. Doubtless its effects on the world in general are only beginning to be comprehended. The writer knows of no other phenomena, geological or biological, which so well characterize the Pleistocene period as do those comprehended under the term Glacial. They constitute the key to the determination of the subdivisions of the epoch and of their succession and to the history of the vertebrates which during this time occupied the continent.

The Blanco is held to belong to the upper, or to the uppermost, Pliocene. It is at present assigned to the Middle Pliocene . Until recently the oldest known Pleistocene vertebrates appeared to be represented by the collections which long ago were made at Fossil Lake, Oregon, and at Grayson , Nebraska. These assemblages had formerly been referred to the Pliocene, and the belief that they belong there is not yet wholly without supporters. It seemed, therefore, proper to retire the Blanco somewhat. The discovery that the Fossil Lake and Grayson faunas were represented in the Aftonian deposits of Iowa, and belonged probably to the first interglacial stage, reveals the fact that the geological interval between the Blanco and the Aftonian is at least partly filled by the first glacial stage, the Nebraskan. Naturally, it is to be expected that the breach between the earlier and the later faunas will be occupied, in part at least, by the vertebrates of the Nebraskan. What these are is not yet well determined; but the writer believes that as the Blanco and its equivalent and closely related formations and faunas become better known, they will be attracted close to the Pleistocene.

Aside from the facts just mentioned, the Blanco fauna seems to the writer to be more closely related to the Aftonian than has been supposed. The genera which occur in the Blanco are the following:

Megalonyx. Mylodon. Glyptotherium. Hipparion. Pliohippus. Protohippus. Platygonus. Pliauchenia. Anancus. Gomphotherium. Stegomastodon. Felis. Amphicyon? Borophagus. Canimartes.

The writer, therefore, ventures to range the Blanco immediately below the Pleistocene. On about the same level may be placed the Tulare-Etchegoin and the Thousand Creek formations of Merriam .

The characteristics of the various stages will be briefly discussed. The stages are not equally well understood and at present do not seem to be of equal importance in their relation to vertebrate paleontology.

In pursuing the study of the Pleistocene, one soon realizes that this period was one of great geological activity. Ranges of mountains, if not begun anew, were at least raised to greater altitudes. The Cascade Range appears to have begun to rear its head at the beginning of the epoch, or even a little later. Here and there the crust of the earth was ruptured and great sheets of lava were poured out over the land. Ice caps repeatedly accumulated over large areas in North America and Europe, and in their movements southward transported vast amounts of earthy d?bris and turned the courses of great streams. Apparently at times the rainfall was greatly increased. The rivers, quickened by greater slope and the increased volume of water, cut their channels deeper and in the mountains excavated profound gorges. Through elevation of the land North America was, late in the Pliocene or early in the Pleistocene, put into easy communication with Asia and South America, so that vertebrated animals passed freely to and fro. A part of these activities probably belonged to the latter part of the Pliocene. In the more elevated regions of the eastern United States, through the chemical, rupturing, and transporting properties of water, rocks were dissolved and their disintegrated materials produced what has been designated the Lafayette formation; but it is possible that this belongs to the early Pleistocene.

Mention has just been made of a land connection with Asia at some time about the beginning of the Pleistocene. The evidence for this may be called circumstantial rather than direct. The geological evidence has not been developed. If any deposits containing marine fossils had been laid down along the Asiatic and Alaskan coasts during a time of elevation, they would now be covered by the sea. Our evidence for the connection is derived from the distribution of the vertebrate animals. During the early Pleistocene our country was invaded by a host of mammals whose home was originally in Asia. These included elephants, bisons, elk, goats, bears, wolves, and foxes, besides many mammals of smaller size. It is the presence in America of the smaller animals, many genera of rodents of Asiatic origin, that shows that there must have been a land connection. These could not have made their passage across Bering Strait on the ice, as it might be imagined the larger animals did.

The way between the two continents had more than once before been open, but it was during the early Pleistocene that modern Asiatic genera entered North America in great numbers. Exactly where the land bridge between the two countries was situated is not certain; it may be that a large part of the area now occupied by Bering Sea was then dry land. Arldt represents a connection extending from the northern border of Alaska southward to include the Aleutian Islands. Where narrowest, this bridge, as represented by the author named, extended from latitude 60? to 70?, a distance of about 700 miles. In such case the cold currents from the Arctic Ocean would have been prevented from entering the Pacific, while the Japan Current would have warmed up the southern side of the bridge. The route was then open on the north for the boreal animals of Asia to enter Alaska; while on the south the genera inhabiting the more temperate part of eastern Asia would have had free access to the American shore. Once on the continent, the boreal mammals might have spread along the shores of the Arctic Ocean and those of the temperate parts of Asia have made their way up the Yukon Valley, or possibly along the Pacific coast, to the warmer regions toward the south. We do not need to suppose that even during the first glacial, or Nebraskan, stage the climate of that part of North America was as inclement as now.

Upon a continent of vast extent and great fertility, possessing unbounded variety of climate and habitat, all these animals were thrown together to struggle for their existence. We must depend upon the imagination to picture what the result would have been if nature had pursued a course which might have been predicted. What the result in reality was, we shall see.

It will be profitable to consider briefly the character of the Pleistocene vertebrate fauna. The writer has compiled a list of the species which have, so far as he knows, been collected and described up to this time. There are in all 637 species; of these, 387 belong to the mammals, 154 to the birds, 26 only to the reptiles, 7 to the amphibians, 56 to the bony fishes, and 7 to the group of sharks and rays. Certainly these form only a part of the species which existed. At present there are known in our existing fauna north of Mexico 693 species of mammals, excluding the cetaceans--somewhat more than twice the number of known Pleistocene species. It is, however, rather in the great variety of forms that the Pleistocene excelled. Following Gerrit S. Miller's Land Mammals of North America, 1912, we find in our present fauna north of Mexico 29 families; in the Pleistocene there are now known 37 families, not including the cetaceans. In our existing mammalian fauna there are recognized 111 genera; in the Pleistocene, with hardly half as many species recorded, 138 genera are counted. In order to realize more vividly the variety of Pleistocene forms, we have only to recall the animals then present, now absent, namely, the great ground-sloths, the glyptodons, the numerous species of horses, tapirs, numerous peccaries, camels, the extinct relatives of the musk-oxen, extinct bisons, elephants, mastodons of three or four genera, the giant beaver, and the saber-tooth tigers. Among the birds, reptiles, batrachians, and fishes, there were few striking forms, and these were mostly among the birds and the tortoises.

The above account shows the great richness of the vertebrate life during the Pleistocene; furthermore, this abundance evidently existed during the early stages of the epoch. It constituted the materials on which that combination of conditions which we call environment had to work during Pleistocene times. The comparison shows that the result was an impoverishment of the vertebrate fauna. Genera and families, even orders, were wiped out of existence, and these included some of the noblest animals that have graced the face of the earth, the elephants, the mastodons, tapirs, many species of bison, horses, saber-tooth cats, huge tigers, and gigantic wolves. The following nine or ten families became either wholly extinct or continued to exist only in other more hospitable lands: the Megatheriidae, including several genera of ground-sloths; the Hoplophoridae or glyptodons; the Caviidae, which embraced one or more species of huge capybaras; the Elephantidae, under which are arranged three or four species of elephants and three genera of mastodons; the Equidae, represented by a dozen or more species of horses; the Camelidae, of which there were several Pleistocene species and probably three or four genera; the Hyaenidae, of which there appears to have been at least one genus, with one species; the Tapiridae, including three or four species; and probably the Rhinocerotidae. Besides these, the subfamily of Felidae known as Machairodontinae, embracing those wonderful carnivores the saber-tooth tigers, was suppressed. The Dasypodidae, which included some armadillos 5 or 6 feet long, are now represented by only one small species in Texas. Of the Tagassuidae, to which belonged several genera and stately species of peccaries, there exists now in North America north of Mexico but one species, an animal of only moderate size.

We have seen that the Pleistocene fauna was very different from that which existed when white men first entered the country; also that the difference has in large part been due to the destruction of species, genera, and families. We may now inquire whether or not the loss has been to any considerable extent compensated by the development of new forms. Many of our existing genera and species have been found in the collections that represent the earliest Pleistocene known to us. The writer believes it would be unsafe to say that any living species that one might select may not hereafter be discovered in early Pleistocene collections. It is probably true, however, that some of those small changes by which we distinguish one species from another have been produced. Some small but persistent differences might, for example, have arisen in the teeth or in the form of the skull of a group of muskrats which would justify us in regarding it as forming a new species. It is extremely doubtful that any new genus of vertebrates has been developed since the first interglacial stage. Matthew has concluded that the evolution of the mammals during the Pleistocene amounts to about one-tenth of that achieved during the Pliocene. The present writer regards this as a liberal estimate.

This failure to evolve new genera and species is not necessarily to be attributed to the shortness of the Pleistocene period; it may have been due rather to the unfavorable conditions. In what direction could an animal make progress when, after being subjected for some thousands of years to one set of conditions, it was compelled for some other thousands to endure just the opposite conditions? If life in front of a glacier for some centuries led to the development of a coat of hair on an elephant, that coat would probably disappear during the succeeding interglacial stage, and in the end, if the elephant had not perished, he would be where he began.

Too much stress must not, however, be placed on this suggestion. It may yet be possible to show that nowhere in the world was any considerable progress made by mammals during the Pleistocene, in the modification of their forms and structure. On the other hand, it is also possible that all over the world climatic conditions were at intervals unfavorably affected by the development of the great glaciers and that all life was retarded in its evolution. The writer believes, therefore, that it can not be shown with certainty that new forms of living things, especially vertebrates, were developed in North America during the Pleistocene. It may be quite as difficult to prove that any genera or species of importance entered from other lands after the first invasion. Under these conditions there appears to be no means for determining successive faunas other than through recording the time of the disappearance of genera and species.

At the beginning of the Pleistocene there existed, as has been shown, an abundant and highly varied mammalian fauna; at the close of the epoch this fauna had become relatively impoverished. Did all those families and genera and species, that in the end were missing, perish during or after the last glacial stage, the Wisconsin? This opinion has been expressed by some. The writer believes that this view is wholly improbable.

A glacial sheet, stretched across the continent or a large part of it, was not local in its effects; it was not a cap of ice merely concealing a part of the land and covered possibly by forests and allowing occupation by certain hardy animals, while beyond, up to its foot, the country was pleasantly cool, wooded, and abounding with animated creatures. In the Sierra Nevada Mountains of California and of Nevada and in the San Juan Mountains of Colorado , at distances of approximately 600 or 700 miles from the glacial front, there existed, during more than one stage, extensive local glaciers. Along the Atlantic coast during at least one glacial stage the walrus was driven as far south as Charleston, South Carolina. One can hardly doubt that the whole continent was chilled during each of the glacial stages.

To mammals, which for perhaps various reasons had been with difficulty enduring the stress of existence, the glacial climates would give the final stroke; perhaps to others the interglacial climates would have been quite as fatal. We can not doubt that each glacial and each interglacial stage swept away a few of the less hardy genera and species. Nevertheless, several remarkable animals passed through the vicissitudes of all the glacial and interglacial times and left their bones in the deposits overlying the last, or Wisconsin, drift. Such are two species of elephants, the American mastodon, the giant beaver, and one or more species of peccaries. Why they succumbed at last is difficult to say. Possibly the return of a fifth warm era proved too much for their endurance.

A reason for believing that the genera and species missing from the fauna found here when white men arrived, called sometimes the Columbian fauna, were exterminated gradually and not at one epoch is that certain ones are found in deposits overlying the earlier glacial drift-sheets, but are not found in deposits on later drifts. Camels occur in Aftonian beds overlying the Nebraskan drift, but have not been collected in later interglacial deposits. Horses grow scarcer as the Pleistocene advances. They are known from deposits overlying the Illinoian drift, but do not appear after the Wisconsin.

It is necessary to determine, if possible, where the boundary line shall be drawn between the Pliocene and the Pleistocene. Room must be made for the first interglacial, the Nebraskan, and its fauna. How long this first glacial stage continued we do not know. Chamberlin and Salisbury have indicated that in a rough way the dates from the present of the culmination of the various glacial stages, except the Nebraskan, taken in order backward, may be represented by the geometrical series 1, 2, 4, 8, 16. That is, if the Illinoian stage had its culmination 150,000 years ago, that of the Kansan occurred 300,000 years ago; if the Nebraskan should fall in the same series, it culminated 600,000 years ago; and it and the succeeding Aftonian interglacial held sway as long as all the rest of the Pleistocene put together. It would be rash to assert that this first glacial did last so long; but we see the possibilities. In a personal communication Professor Frank Leverett writes that he estimates that the Kansan culmination took place at not less than 400,000 years ago and the Nebraskan at 500,000. This, as the present writer estimates, would leave for the Nebraskan itself somewhere near 40,000 or 50,000 years. Some changes in the life of the Pleistocene must have been wrought during those years.

The glacial deposits of the Nebraskan stage are not as well known as one might wish. They appear to be in general overlain by the later drifts and are observed mostly where streams have cut through both the overlying drift and the Nebraskan. The old drift found in New Jersey is thin and of no great extent. Moreover, we can hardly expect to find fossil vertebrates in the drift itself. We must therefore depend on studies of supposed Nebraskan fossils found mostly outside of the glaciated area and make comparison of them with earlier and later faunas. If we shall discover collections of Nebraskan vertebrate animals, we may be sure that they will differ from those of the first interglacial, the Aftonian. We may be pretty certain that they will include autochthonous genera of the late Tertiary, which may be missing from the Aftonian, together with at least a few genera from South America and others from Asia.

Now, have any formations and included fossil vertebrates been found which may be fitted into the Nebraskan interval?

In this stage the writer places the beds which Cope designated the Idaho formation . Since Cope's time several new species have been added to his list from this formation. In 1917 , Dr. J. C. Merriam published a list of the fossils, except fishes, which had been secured up to that time. The list of species referred to the Idaho formation is as follows:

Equus idahoensis. E. excelsus? Protohippus? Rhinoceros, probably Aphelops fossiger. Mastodon mirificus. Cervus, possibly new. Smaller and more slender than C. canadensis. Procamelus, size of P. major. Tragocerus? horn-core of antelope. Ischyrosmilus n. sp. Morotherium leptonyx. Castor, possibly n. sp. Olor, size of O. paloregonus. Graculus idahoensis.

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