Early Man in Britain and His Place in the Tertiary Period

Front matter

EARLY MAN IN BRITAIN

AND

HIS PLACE IN THE TERTIARY PERIOD

List of Illustrations

LIST OF ILLUSTRATIONS.

J. S. Gardner, Nature, xv. p. 231.

Judd, Quart. Journ. Geol. Soc. Lond., xxx. Pl. xxiii.

Self, Q. J. G. S., xxxiv. p. 205.

Self, Q. J. G. S., xxxiv. p. 405.

Self, Q. J. G. S., xxiv. p. 408.

Self, Q. J. G. S., xxxiv. p. 408.

Self, Q. J. G. S., xxxiv. p. 417.

Self, Q. J. G. S., xxxiv. p. 412.

Capellini, Letta alia Reale Acad. dei Lincei, 7th May 1876, Pl. iii. Fig. 2.

Self, Q. J. G. S., xxxi. p. 251.

Self, Cave-hunting, Fig. 82.

Lartet, Reliquiæ Aquitanicæ, B, Pl. xxviii.

Self, Q. J. G. S., xxxi. p. 251.

Self, Q. J. G. S., xxviii. p. 436.

Self, Q. J. G. S., xxviii. p. 407.

Cheadle and Woodward, Proc. West Lond. Scient. Ass., Sept. 1876, p. 5.

Self, Q. J. G. S., xxiii. p. 92.

Self, Nat. Hist. Rev. 1863, p. 410.

Do. p. 405.

Self, Q. J. G. S., xxiii. p. 96.

Self, Cave-hunting, Fig. 126.

Evans, Ancient Stone Implements, Fig. 451.

Lane Fox, Q. J. G. S., xxviii. p. 455.

Do. p. 455.

Medlicott, Records of Geological Survey of India, 3, 1873, p. 51.

Wyatt, Q. J. G. S. xx. p. 185.

Evans, Ancient Stone Implements, Fig. 449.

Mello, Q. J. G. S., xxxi. p. 671.

Mello, Q. J. G. S., xxxii. p. 242.

Self, Q. J. G. S., xxxii. p. 250.

Do. p. 250.

Do. p. 251.

Self, Q. J. G. S., xxxiii. p. 593.

Do. xxii. p. 253.

Do. p. 252.

Do. p. 254.

Do. p. 253.

Self, Q. J. G. S., xxxiii. p. 603.

Do. p. 592.

Do. p. 603.

Do. p. 603.

Do. p. 603.

Do. p. 603.

Do. p. 594.

Do. p. 725.

Self, Q. J. G. S., xviii. p. 118.

Pengelly, Journ. Plym. Inst. 1875, Fig. 10.

Evans, Ancient Stone Implements, Fig. 386.

Do. Fig. 390.

Do. p. 457, Fig. 402.

Do. Figs. 403, 404.

Lartet and Christy, Rel. Aq., A, Pl. iv. Fig. 2

Do. Pl. vi. Fig. 3.

Do. Rel. Aq., B, Pl. xvii. Fig. 10.

Do. B, Pl. xiv. Fig. 3. Do. B, Pl. i. Fig. 6.

Lartet and Christy, Rel. Aq., B, Pl. xiv. Fig. 4.

Do. p. 65, Fig. 39.

Do. p. 67, Fig. 41.

L. Lartet and Chaplain-Duparc, Matériaux, 1874, p. 141.

Do. p. 139.

Massenat, Matériaux, 1869, p. 348, Pl. xxxiii. Fig. 1.

Lartet and Christy, Rel. Aq., B, Pl. ii. Fig. 8.

Lartet and Christy, Rel. Aq., Pl. xxiv.. Fig. 40.

Hamy, Paléontologie Humaine, p. 208.

L. Lartet and Chaplain-Duparc, Matériaux, 1874, p. 143.

Massenat, Matériaux, 1869, p. 348, Pl. xxxiii. Fig. 2.

Lartet and Chaplain-Duparc, Matériaux, 1874, p. 142.

Lartet and Christy, Rel. Aq., B, Pl. vii. Fig. 6, c.

Heim, Mit. der Antiq. Gesellsch. im Zurich, xviii. p. 136.

Lartet and Christy, Rel. Aq., B. xxiv. Fig. 5.

L. Lartet and Chaplain-Duparc, Matériaux, 1874, p. 101 et seq.

Self, Cave-hunting, Fig. 124.

Do. Fig. 122.

Perrin, Etudes Préhist. sur la Savoie, 1870, Pl. i. Fig. 2.

Self, Cave-hunting, Fig. 123.

Do. Fig. 125.

Massenat, Matériaux, 1869, p. 348.

Stevens, Private lithograph.

Mudge, Archæologia, xxvi. Pl. xlvii.

Self, Cave-hunting, Fig. 38.

Keller, Lake-dwellings, 2d edit. Pl. xi. Fig. 1.

Greenwell, Ethnol. Soc. Journ., ii. p. 419.

Lane Fox, Journ. Anthrop. Inst. v. Pl. xiv.

Thurnam, Archæologia, xlii. Fig. 8.

Do. Fig. 7.

Do. Fig. 9.

Montelius, Congr. Inst. Archéol. Préhist., Stockholm, p. 474.

Thurnam, Mem. Anthrop. Soc. i. p. 153.

Do. i. p. 152.

Self, Cave-hunting, Fig. 68.

Broca, Mem. Soc. Anthrop. de Paris, i. p. 1, iii. p. 224.

Thurnam, Archæologia, xliii. Fig. 156.

Do. Fig. 157.

Lane Fox, Royal United Service Inst. xiii., Primitive Warfare, Jan. 10, 1869, Fig. 117.

Evans, Petit Album de l'Age du Bronze, iv. p. 2.

Lane Fox, Op. cit., Fig. 118.

Thurnam, Archæologia, xliii. Fig. 148.

Lane Fox, Op. cit., Fig. 120.

Evans, Petit Album de l'Age du Bronze, Pl. vi. Fig. 1.

Franks, Archeol. Journ. ix. p. 7.

Thurnam, Archæologia, xliii. Fig. 194.

Do. Figs. 213-217.

Do. Fig. 114.

Wilson, Prehistoric Annals of Scotland, Fig. 70.

Thurnam, Archæologia, xliii. Fig. 83.

Do. Fig. 50.

Greenwell, Proceed. Soc. Antiq., SS. ii. p. 177.

130 Thurnam, Archæologia, xliii. Fig. 177. 131 Thurnam, Proceed. Soc. Antiq., SS. v. p. 429, Pl. iv. Fig. 13.

Proceed. Soc. Antiq., SS. ii. p. 429.

134 Greenwell, Proceed. Soc. Antiq., SS. ii. p. 177. 135-6 Do. SS. v. Pl. 429, Figs. 16, 17.

Thurnam, Archæologia, xliii. Fig. 3.

Do. Fig. 2.

Do. Fig. 6.

Do. Fig. 96.

Do. Fig. 10.

Fergusson, Rude Stone Monuments, Fig. 14.

Stevens, Jottings of Stonehenge Excursion, Salisbury Meeting of Wilts Archeol. and Nat. Hist. Soc., Fig. 59.

Brown, in Stevens, Op. cit., Fig. 58.

Stevens, Op. cit., Fig. 60.

Stevens, Op. cit., Fig. 62.

Chantre, L'Age du Bronze, 1st part, p. 236.

Worsaae, Primeval Antiquities, p. 34.

Do. p. 30.

Do. p. 39.

Do. p. 31.

Do. p. 36.

Lorange, Congr. Int. Archéol. Préhist. Stockholm, p. 460.

Lorange, Op. cit., p. 454.

Montelius, Congr. Int. Archéol. Préhist. Stockholm, Fig. 90.

Simonin, La Vie Souterraine, Fig. 136, p. 483.

Wilson, Prehist. Annals of Scotland, 1. Fig. 68, p. 397.

Wilde, Catal. R. I. Acad., Gold, Fig. 537.

Wilson, Prehist. Annals of Scotland, ii. Fig. 131.

Gage, Archæologia, xxvi. p. 422.

Kemble and Franks, Horæ Ferales, Pl. xvii.

Wilson, Prehist. Ann. Scotl. ii., Fig. 143.

Keller, Lake Dwellings, 2d edit., Pl. cxxii. Fig. 1.

Lorange, Congr. Int. Archéol. Préhist. Stockholm, p. 459.

Self, Cave-hunting, Fig. 25.

Stuart, Sculptured Stones of Scotland, Spalding Club, Pl. 67.

CORRECTIONS AND ADDITIONS.

Page | | 10, | lines 12, 16, 19, for grave accent, read acute.

| „ | | 17, | line | 15, before "con" insert "and."

| „ | | 22, | | „ | 21, for "500," read "from 500 to 600."

| „ | | 39, | | „ | 6, for "squirrels," read "Rodents, the Viverra, Mustela, Rhinoceros."

| „ | | 40, | in Lower Meiocene Table insert "Viverra, Mustela, Rhinoceros."

| „ | | 57, | line | 25, for "Eocene," read " Meiocene."

| „ | | 84, | note, for "florentinus. Cocchi, Aulaxinus," read "(Aulaximis) florentinus, Cocchi, and a second not yet named."

| „ | | 90, | line | 11, for "Pleiocene," read "Pleistocene."

| „ | | 95, | | „ | 20, insert "?"

| „ | 104, | | „ | 19, dele "Falconer's elephant."

| „ | 113, | | „ | 28, dele "the."

| „ | 128, | | „ | 21, insert "?"

| „ | 128, | to "New Comers" add "the squirrel, Sciurus vulgaris, Lin."

| „ | 138, | line | 5, dele "pouched."

| „ | 147, | to "Survivals—Living Species" add "Musk sheep," and to "Extinct Species" add "Machairodus."

| „ | 213, | fig. 77, for "Duruthy," read "Laugerie Basse."

| „ | 239, | | „ | 94, for "Haute," read "Basse."

| „ | 159, | line | 259, line 11, dele "and Ireland."

| „ | | 478, | The abundance of apples mentioned by Pytheas in Thule proves that Thule was not either Iceland, the Faröes, the Hebrides, or the Orkneys, but, as Nilsson remarks, the south of the Scandinavian Peninsula.

Chapter I

EARLY MAN IN BRITAIN.

CHAPTER I.

THE RELATION OF GEOLOGY TO ARCHAÆOLOGY AND HISTORY.

The Continuity between these three Sciences.—The three Phases of Life on the Earth.—These three Phases universal—Breaks in the Succession accompanied by Geographical Change.—The History of Tertiary Life ends with Man.—The Classification of the Tertiary Period.—The Specialisation of the Mammalia explained by the Theory of Evolution.

Of the many fields of inquiry opened out by the intense mental activity of this century, there is none which promises to be more fruitful than that which has been won by the joint labours of the geologist, the student of prehistoric archæology, and the historian. The geologist, beginning his story of the earth at the time when the rains first descended and the seas first began to beat on the coast-lines, has laid, as it were, in a map before us the revolutions in climate and geography that it has undergone. He tells of continents submerged, and of ocean bottoms lifted up to become mountains; and he points out to us that side by side with the ever-changing conditions of life there were corresponding changes in the living forms. Group after group of animals and plants pass over the field of vision, each connected with that which preceded it, and each becoming more and more highly organised, until man appears the last born as well as the highest and the noblest creature in the realm of geology.

The archæologists in the meanwhile have raised the study of antiquities to the rank of a science by the use of a purely inductive method, and have accumulated materials which enable us to establish a tolerably complete sequence of events from the remote past in which man stands in the geological foreground down to the borders of history. To them we owe the knowledge of the steps by which man slowly freed himself from the bondage of the natural conditions under which all other creatures live; of the successive discoveries of the use of polished stone, bronze, and iron; of the domestication of animals; of the cultivation of the fruits of the earth; of the introduction of the arts; in a word, of all those things by which man has become what the historian finds him.

The writers of history—Freeman, Green, Stubbs, Guest, and others—have carefully sifted the true from the false, the certain from the uncertain, in the records of this country, and have consolidated, so to speak, their domain, so that it can be used by the archæologist as a base for the conquest of what lies beyond. If, however, in this respect, archæology be indebted to historical criticism, she is now in a position to repay the debt with ample interest. In the pages of the historian, man appears in the high state of civilisation marked by the use of letters, and the written record is silent as to his progress up to that point. The steps by which that civilisation was achieved are pointed out by prehistoric archæology, and these are traced back until man is discovered living under conditions wholly unlike those which are now experienced in this country, under a different climate and a different geography, and surrounded by wild animals, for the most part unlike any now to be found in Europe.

The Continuity between these three Sciences.

The continuity between geology, prehistoric archæology, and history is so direct that it is impossible to picture early man in this country without using the results of all these three sciences. The history of the earth is necessary to the history of man, if a broad view be taken instead of a narrow specialism flowing from the tendency of the age towards minuteness of detail. In the earliest records the inhabitants of this country, about two thousand years ago, are represented as being similar in their habits and modes of life to their neighbours in Gaul, and we gather from Cæsar's Commentaries and the Agricola of Tacitus that they were composed of the same Belgic, Celtic, and Iberic tribes, in the stage of culture marked by the use of iron,—foes by no means despicable to the Roman legions. The accounts, however, which have been handed down to us have been written merely from a military point of view, and from them we learn very little of the life, of the arts and habitations of the Britons of those times, and still less of the condition of the country, of the extent of forest and morass, and of the wild animals which they sheltered. On all these points modern discoveries draw aside the veil, and we can form almost as clear an idea of the inhabitants before the landing of Julius Cæsar, and of their internal and external relations, as we can of those who dwelt in Britain for the first two centuries afterwards. We know that they carried on a commerce and possessed a coinage, how they lived, and how they buried their dead. The tomb on the lonely moor or the swelling chalk-down, the habitation within the earthen or rock-built rampart, the camps in the best military positions commanding the pastures, the discoveries in dredging the rivers or in draining the morasses, offer the materials for bringing the life of those men before our eyes. But we can do more than this; we can indicate their advance in culture and the changes wrought in their conditions of life. We can follow them back to a time when they were on the continent, and trace their westward progress over Europe from their ancient Eastern home, from the birthplace of the nations, Asgard, the mystic Garden of Eden. We can prove that they were composed of two distinct elements, the older or the non-Aryan Iberic, and the later or the Celtic, forming the vanguard of the great army of the Aryan invaders; we know to what extent our civilisation is due to them, and how they were influenced by the civilised peoples of the Mediterranean, Phœnicians, Greeks, Etruskans, and Romans. The ancient routes of trade, leading from the Mediterranean and Black Sea northwards as far as Scandinavia and Britain, have also been traced, and we can indicate with tolerable precision what we may term the overlap of history. We are now able to realise that, while Egypt and Assyria were highly civilised and mighty empires, while the Greeks were extending their influence and power over the Mediterranean, while the Etruskans still ruled over Lombardy, and while the Phœnicians were pushing their trade farther and farther northwards along the shores of the Atlantic, the inhabitants of middle Europe were gradually passing from the Bronze stage of culture into that of Iron. The knowledge of Bronze was spreading northwards, and the lower Neolithic civilisation, characterised by the use of polished stone, and the ignorance of metals, formerly universal, was disappearing from the more remote portions of the continent.

Our inquiry into the progress of man reaches back to a time far more distant than any of these events. Before our ancestors were in Europe, and before our country was an island, there were Palæolithic tribes in Britain, ignorant of the use of polished stone and of the metals, without domestic animals, living solely by the chase, fishing, and fowling; of these, the older or the River-drift men, have left evidence that they wandered over the greater part of western and southern Europe, over North Africa, Asia Minor, and over the whole of India; while the newer, or the Cave men, have been traced over a large part of Europe. Their mode of life, and their relation to living races of men, the time of their arrival in Europe as marked in the geological record, and their surroundings, cannot fail to be of high interest to all thoughtful men.

In dealing with these difficult questions I propose to place before the reader a definite idea of the various changes which have taken place in Britain before the written record, and to make early man the central figure in the pictures of the successive changes presented by geology and prehistoric archæology. I have adopted the historical method of beginning with the earliest and working downwards with the current of events, rather than that more usually adopted of ascending the stream of time from the point of departure offered by the written record. The appearance and disappearance of successive groups of wild animals, the varying climate and geography, the successive invasions of tribes, the gradual development of civilisation, fall within my scope. The materials necessary for this task are perplexing in their abundance, and lie scattered over a wide field; the progress of discovery is very swift, and there are great blanks in the story yet to be filled in. Nevertheless, after a preparation of many years by researches in this country and on the continent, it seems to me to be better to attempt to perform the task, however imperfectly, rather than to wait for that perfection which perhaps might never come.

The three Phases of Life on the Earth.

The history of life in Europe falls naturally into three great divisions, separated from each other by breaks of great magnitude. In the first or Primary, fishes and amphibians, and in the upper part a few reptiles, were the master beings which have left their traces buried in the rocks. The vegetation, now principally represented by the coal seams, consisted of pines, araucariæ, tree ferns, and gigantic trees (Sigillaria and Lepidodendron and Calamites), allied to the club mosses and marestails. In the second or Secondary, reptiles had the mastery, walking on the land as giant carnivores and herbivores (Iguanodons and Megalosauri), flying in the air as pterodactyles, or huge reptilian bats, swimming in the sea as great reptilian whales, seals, and walruses (Ichthyosauri, Pleiosauri, and Plesiosauri). The birds are represented by the Archæopteryx of Solenhofen, with a long tail Like that of a reptile, and in the Creta rocks of America by the Odontornithes or birds with teeth in their beaks. The remarkable combination of characters in these two widely-different forms renders it probable that the class Aves was not sharply defined from the class Reptilia in the Secondary period. The only mammalia which have been discovered are small marsupials, the largest of which was not larger than a kangaroo-rat. The forests then covering Europe consisted principally of coniferæ, araucariæ, zamiæ, and cycads, and trees with deciduous leaves do not appear until the Cretaceous or concluding phase of the period. In the third or Tertiary period, the higher placental mammals first appear, taking the place of the reptiles of the Secondary in their mastery of land and sea, and flying in the air as bats. The true birds also have left the reptilian characters far behind, and in the vegetable kingdom the angiosperms, both evergreen and with deciduous leaves, increase and multiply, until they assume their present important place in the forests of the world.

These three Phases universal.

These three phases of life may be traced over the whole earth, and their succession is invariable, from which it may be inferred that they are due to causes acting universally, and not sporadically in one or more centres. They prove that the earth as a whole has passed through a series of biological changes, analogous to those which are to be seen in the animal world in the passage from birth to old age. They may be accounted for on the theory of evolution of Herbert Spencer and Darwin, that while the conditions of life were ever changing, those animals and plants which were not sufficiently plastic to conform to a new state of things died out, while those which were more capable of modification, so as to be in harmony with their surroundings, became what we know as new species, genera, families, orders.

Breaks in the Succession accompanied by Geographical Changes.

The succession of living forms has been uninterrupted, although, from errors of observation, as well as from the fragmentary nature of the evidence, it appears to be broken. Each break may be likened to places from which pages, or chapters, or whole volumes, as the case may be, have been torn out from the record by the hand of time, or not yet discovered by man. It must also be observed that the breaks in the succession are invariably accompanied by geographical change of corresponding magnitude. That, for example, which took place at the close of the Secondary period consisted in the elevation of the chalk rocks, which were accumulated at the bottom of the Cretaceous ocean, extending from southern and eastern Britain, through France into the Mediterranean area, Greece, Palestine, Asia Minor, Germany, Russia, and far into Asia, so as to form a continent on which the Eocene mammalia make their appearance. In this case the conditions of life must have been profoundly modified by the geographical change. The climate, must have been altered, and forms of life, which had been previously elaborated outside Europe, would enter into competition with the old European forms on the new continent. The contrast between the Secondary and the Tertiary faunas is enormous and proportionate to the geographical change, but it is not so strongly marked in the floras, which have changed more slowly.

The History of Tertiary Life ends with Man.

The third or Tertiary period is that which more immediately concerns us. In it each life-group is so closely linked to that which went before and followed after, that there is no break of sufficient importance to be used for a starting-point in our special inquiry into the ancient history of man. We shall therefore be compelled to treat in outline the principal changes which took place in this country from the beginning of the Tertiary period down to the time when man first appeared upon the stage, and to see how they are related to the varying conditions of life on the continent.

The Classification of the Tertiary Period.

The Tertiary period in Europe may be divided into six well-defined stages, as I have pointed out in my work on Cave-hunting.

| | | Characteristics.

| | I. Eocene, or that in which the mammalia now on the earth were represented by allied forms belonging to existing orders and families. | | Living orders and families present.

| | II. Meiocene, in which the alliance between living and fossil mammals is more close than before. | | Living genera.

| | III. Pleiocene, in which living species of mammals appear. | | Living species.

| | IV. Pleistocene, in which living species are more abundant than the extinct. Man appears. | | Living species abundant. Man appears.

| | V. Prehistoric, in which domestic animals and cultivated fruits appear, and man has multiplied exceedingly on the earth. | | Man abundant. Domestic animals. Cultivated fruits.

| | VI. Historic, in which the events are recorded in history. | | Historical record.

The Tertiary or Kainozoic strata were divided by Sir Charles Lyell in 1833, into three great groups, according to the percentage of existing mollusca, which was presented in a comparison of 3000 fossil with 5000 living forms. The Eocene (ἠὼς dawn, καινὸς new), or the earliest group, contained about 32/ per cent of living shells, and thus, to speak metaphorically, was characterised by the dawn of the Testaceous fauna, now living in the sea. In the Meiocene (μείων less, καινὸς) group the existing forms were much more abundant, being always less than 35 per cent. The upper group was termed Pleiocene (πλειὼν more, καινὸς), because it presented from 35 to 50 and even 90 per cent of living testacea. The vast number of fossil species which have since been added to those which formed the basis of this classification has not materially altered its value, but merely rendered the strict definition of the percentages impossible. The term Pleistocene (πλειστὸς most, καινὸς) was subsequently applied by Sir Charles Lyell to assemblages of fossil species in which there was a still nearer approximation to existing nature.

The idea of percentages of living among extinct species implied by the etymology of the first four terms has been so modified by modern discoveries that I have substituted for the more usual definitions those which are in harmony with our present knowledge, taking the most highly specialised animals as my guides, which alone have changed swiftly enough to be used to classify the subdivisions of the Tertiary period. The Prehistoric and Historic stages constitute the Recent division of Lyell and most other authors, and the evidence on which they, as well as the Pleistocene, are included in the Tertiary period will be placed before the reader in the course of this work.

The Specialisation of the Mammalia explained by the Theory of Evolution.

The argument in favour of the theory of evolution, founded on the specialisation of mammalian life, in its progress from the Eocene times down to the present day, seems to me so strong as to be almost irresistible. The facts are put into a tangible shape in the accompanying diagram (Fig. 1), in which it will be observed that the orders, families, genera, and species fall into the shape of a genealogical tree, with its trunk hidden in the Secondary period, and its branchlets, the living species, passing upwards from the Pleiocene, Pleistocene, and Prehistoric stages to the present time—a tree of life with living mammalia for its fruit and foliage. Were the extinct species taken into account, it would be seen that they fill in the intervals separating one living form from another, and that they grow more and more like the living forms as they approach nearer to the present day. These facts appear to me inexplicable on any other theory than that of evolution.

Fig. 1.—Specialisation of Mammalia in Tertiary Period.

No similar series of changes such as these has been observed in the reptiles, amphibians, fishes, or in the Invertebrates of the Tertiary strata, nor is it clearly marked in the Tertiary vegetation. In the birds, however, a similar specialisation has been pointed out by Professor Milne Edwards. The living orders, families, and genera of the lower Vertebrates had already appeared in the Primary and Secondary periods; first, the lower and afterwards the higher forms, preserving in their successive appearances the order in which they are arranged in the classification of the naturalists.

Chapter II

CHAPTER II.

BIOLOGICAL AND PHYSICAL CHANGES IN BRITAIN BEFORE THE ARRIVAL OF MAN.—THE EOCENE PERIOD.

The Eocene Classification.—South-Eastern Coast-Line of Britain.—Eocene Sea-Board of Britain.—The Eocene Sea.—Britain connected with America.—The Mountains.—The Rivers.—The Lower Eocene Plants and Animals.— The Lower Eocene Birds.—The Mid Eocene Flora.—The Mid Eocene Mammalia.—British Upper Eocene Mammals.—Upper Eocene Mammalia of the Continent.—The Order Primates represented.—Climate of Britain Tropical.—General Conclusions.—Man not here.

The close of the Secondary age, as we have observed in the preceding chapter, was marked by great changes in the physical geography of Europe. The cretaceous rocks, which had been formed at the bottom of a deep sea, were lifted up above the waves, and plants and animals hitherto unknown appeared on the new continent. The new invaders took possession of the land, the air, and the sea, and brought about as marked a change in the European fauna as that in geography which had preceded their arrival.

It is very probable that the elevation of the bottom of the sea, by which this immigration of new forms became possible, was accompanied by a corresponding depression of a neighbouring tract of land, like that which took place in the Pleistocene age, when the Sahara Desert was covered by the sea, and a large part of the Mediterranean area was dry laud, or like that now taking place in the Scandinavian peninsula, which is being lifted up from the North Cape to Stockholm, and depressed in the south, in Scania. New conditions of life were produced by these changes, so unfavourable for the Secondary animals, that all the higher forms perished that were unable to compete in the struggle for life with the new invaders, whose presence marks the Eocene period. The invasion of Europe by the placental mammals is the great event which is the natural starting-point for our enquiry into the ancient history of man, since the conditions by which he was surrounded on his arrival in Europe, form part of a continuous sequence of changes, from that remote period down to the present day. Each of these changes in life and geography will be treated in outline in its due place in this work.

The Eocene Classification.

The Eocene period has been defined in the last chapter as that in which the existing orders and families of the placental mammalia appear for the first time. The Eocene marsupials, however, are, as may be expected from their class having appeared in the Secondary age, in a far more advanced stage of evolution, being represented by a living genus, the opossum, as well as by other forms intermediate between the marsupials and the true placental mammals.

The Eocene strata are found in the area to the south-east of a line passing from the Wash to Charmouth in Dorsetshire, and are mainly centered in two basins, named, respectively, that of London, and that of Hampshire and the Isle of Wight. They occur over a very wide area on the continent. They are divided into three groups, the lower or Pre-nummulitic, the middle or the Nummulitic, and the upper or the Post-nummulitic, the widely spread foraminifer, Nummulites (Fig. 2), offering a ready means of determination of age, not merely in Europe, but throughout Asia, and a large part of Africa. The following table represents the thickness, characters, and conditions of deposit of each of the subdivisions in England, together with their equivalents in France, as determined by the recent researches of Professor Gaudry.

Classification of British Eocene Strata.

1. Upper Eocene or Post-nummulitic = Proicène (Gervais).

| Thickness in Feet. | | Conditions of Deposit. | | French Equilavents (Gaudry).

| 170 | | | |

| 80 | | | | | 6e Étage du Gypse de Paris.

| 100 | | | |

| 260 | | | |

2. Middle Eocene or Post-nummulitic = Eocène (Gervais).

| 300 | | | | | 5e Étage des Sables de Beauchamp.

| Bracklesham Bagshot | | | | | | ? | | | | | 4e Étage du Calcaire Grosier de Paris.

| Alum Bay and Bournemouth | | | | | | ? | | | |

3. Lower Eocene or Pre-nummulitic = Orthocène (Gervais).

| 480 | | | | | 3e Étage des Sables de Cuyse-la-Motte, Sables de Soissonnais.