Early Man in Britain and His Place in the Tertiary Period/Chapter 3
CHAPTER III.
BIOLOGICAL AND PHYSICAL CHANGES IN BRITAIN BEFORE THE ARRIVAL OF MAN.—THE MEIOCENE PERIOD.
We have, in the course of this chapter, to seek for evidence of man in the Meiocene life period, when the living genera of mammals first begin to appear. It must be admitted that the strict definition of the Meiocene from the Eocene period is one of exceeding difficulty from the imperfect preservation of the fossils, and from the impossibility of ascertaining the exact relative age of assemblies of animals found in isolated lake basins and in river deposits widely remote from each other. The only clue to their geological date is the stage of evolution presented by the mammalia, the more general having obviously preceded in point of time the more special forms.
The Meiocene Classification.
The Meiocene fauna and flora of Britain are but insignificant fragments of those found in the strata occupying a vast area in Europe, south of a line passing through Antwerp, and represented in northern Germany and Denmark by outliers or isolated parts of what were once probably continuous formations. For the purposes of this chapter, the vegetation will be considered in one group, while the mammalia will be treated in three groups—a Lower, Middle, and Upper. It must, however, be remarked that there is less difference between these than between the like divisions of the Eocene described in the last chapter.
The following table represents the Meiocene classification, according to Heer, Gaudry, and Forsyth Major, the two latter using the mammalia as their principal means of determining relative age:—
Table of Meiocene Classification.
| Britain. | Switzerland. (Heer). |
France and Germany. (Gaudry). |
Italy. (Forsyth Major). | |
| Upper. | Freshwater molasse =Πningian zone. |
Léberonian of Mont Léberon. Eppelsheimian of Eppelsheim. |
Lignites of Casino, near Sienna. | |
| Middle. | Marine molasse =Helvetian zone. |
Simorrian of Simorre. Sansanian of Sansan. Orléanaisian of the Orléanais. |
Lignites of Monte Bamboli. | |
| Lower. | Lignites of Bovey Tracey. |
Freshwater molasse=Grey molasse zone. |
Fauna of the Allier (in part) =Zone of the Calcaire de Beauce. |
|
| Vegetable accumulation under lava in Hebrides and North of Ireland. The Hempstead beds. |
Lower brown coal= Aquitanian zone. Tongrian zone (marine). |
Sables de Fontainbleau. |
Lignites of Cadibona. |
Genera of Meiocene Mammalia now living.
The living genera of land mammalia which appear in Europe in the Meiocene age are represented in the following table, based upon the lists given in Appendix II. In it the reader will see that, with the exception of the insectivores, the squirrels, and the tapirs, no living genera of placental mammals have been identified in the lower Meiocene, while the opossum, the last representative of the marsupials in Europe, is not found in either of the later stages.
Range of Living Genera in Meiocenes of Europe.
| Lower Meiocene. France. |
Mid Meiocene. France. |
Upper Meiocene. Middle and S. Europe. | ||||
| Bat, |
|
x | ||||
| Mole, |
|
x | x | |||
| Shrew, |
|
x | ||||
| Water-Shrew, |
|
x | x | |||
| Dormouse, |
|
x | x | |||
| Hedgehog, |
|
x | x | |||
| Squirrel, |
|
x | x | |||
| Beaver, |
|
x | ||||
| Pika, |
|
x | ||||
| Porcupine, |
|
x | ||||
| Cat, |
|
x | ||||
| Hyæna, |
|
x | x | |||
| Otter, |
|
x | ||||
| Viverra, |
|
x | ||||
| Mustela, |
|
x | x | |||
| Gazelle, |
|
x | ||||
| Giraffe, |
|
x | ||||
| Antelope, |
|
x | x | |||
| Deer, |
|
x | x | |||
| Hog, |
|
x | x | |||
| Tapir, |
|
x | x | |||
| Rhinocerus, |
|
x | x | |||
| Opossum, |
|
x |
The Southern Seaboard.
The sea of the Meiocene age touched only one portion of Britain, at Hempstead (Fig. 6), in the Isle of Wight, where strata, 170 feet thick, partly of marine and partly of freshwater origin, are usually considered to belong to the lower Meiocene division.[1]
Fig. 6.—Geography of North-Western Europe in the Meiocene Age.
They have furnished the remains of a small hoglike animal, Hyopotamus bovinus of Owen, which is identified by Professor Gervais with that found in lower Meiocene strata in the Bourbonais. Crocodiles also have been met with, closely resembling those of the lower Meiocene strata of the Boulonnais and valley of the Allier.[2] Among the plants Professor Heer recognises a form analogous to the mammoth tree of California, and three other species identical with those of the lignites of Bovey Tracey.[3]
In the middle and upper Meiocene periods the southern area became lifted up above the waves, and the retreat of the British coast-line southwards towards the mainland of France, which had begun in the Eocene age, was completed by the greater part, if not the whole, of the English Channel becoming dry land.
We may infer, from the rarity of Meiocene deposits in Britain, and from their being, with the above exception, mere freshwater local accumulations, that the mainland of Europe extended northwards, so as to include the British area throughout the middle and later stages of the Meiocene period. The south-eastern sea of the Eocene age (Fig. 3), described in the last chapter, was reduced in the early Meiocene age to two isolated basins, of which one covered the Isle of Wight and the adjacent regions, the southern sea of Fig. 6; while the other extended over Holland and Belgium, but did not come far enough to the west to touch the present coast-line, although its proximity may be inferred from the rolled fragments of Meiocene fossils found in the Pleiocene strata of Norfolk and Suffolk, and derived from the older marine accumulations.
Continuity with North America.
The researches of Professor Heer into the fossil vegetation of the Continent, Britain, Iceland, Spitzbergen, Greenland, and Grinnell-land, prove that the whole of this portion of the earth's surface was dry land in the early Tertiary period, offering free means of migration to plants and animals from the Polar regions into America on the one hand, and Europe on the other. Among the forms common to the Meiocenes of Europe and the flora of the American continent, we may notice the mammoth tree, magnolia, tulip tree, red wood, and swamp cypress (Taxodium disticum); among the mammalia common to both, the Hipparion; among the reptilia, the alligator-tortoise[4] and a frog,[5] allied to the horned species of Brazil. Similar evidence of direct communication between the two continents is afforded by the Meiocene insects[6] and land crabs (Gecarcinus) of Oeningen, in Switzerland. We may therefore conclude that the barrier of land connecting the British area with Iceland and Greenland in the Eocene, existed in the Meiocene age, and allowed plants which were Eocene in the Polar regions to flourish in Meiocene Europe. The five-hundred fathom line indicates the probable coast-line during both ages, and the rapid increase of depth in the Atlantic to its west would allow of a considerable depression taking place, without altering in any important degree the position of the sea-margin.
Professor Heer[7] places his Atlantis to the south-west of the land represented in the map (Fig. 6); but the enormous depth of the North Atlantic renders it very improbable that there was dry land in that region at a time, geologically speaking, so recent as the Meiocene age.
The Mountains.
The principal mountains in the British Isles were in their present positions in the Meiocene age, but were considerably higher. If we take the rate of denudation to be the same as that which we know to have taken place in the volcano of Mull in post-Meiocene times (Fig. 7), which, exclusive of the cone, has been shown by Professor Judd[8] to have been 6000 feet high, while the present height of Beinn More, the highest fragment now remaining, is but 3172 feet, we arrive at the startling result that the height of the Meiocene mountains in Britain was double what it is now. It is therefore probable that in the western and northern parts of our island mountains rose to a height of 6000 or 7000 feet, even if we do not take into account the amount of elevation above the sea necessary to allow of continuity between Britain and Iceland. If the 500 fathoms of elevation of the Meiocene continent be added, the mountains must then have lifted up their heads in Wales, Cumbria, and Scotland not less than about 10,000 feet above the sea.
Volcanoes in British Islands.
Fig. 7.—Section through Beinn More. The dotted line = Meiocene Surface.
The fossil vegetation under the sheets of basalt and of volcanic tufa in the Hebrides and in the north of Ireland, proves that in the north and west of the British Isles there were active volcanoes in the Meiocene age. Some of these were of enormous size. "The base of the volcano of Mull"[9] (Fig. 7), writes Professor Judd, "must have had a circumference of at least forty miles; Etna, which has a greatly truncated cone, nevertheless rises to over the height of 10,900 feet from a base of only thirty miles in circumference. A similar relation between the base and the altitude of the great volcanoes of Sicily and Mull would lead us to infer that the elevation of the latter was at least 14,500 feet." From another calculation, founded on the inclination of the beds of lava, he infers that the volcano of Mull could not have been less than 10,000 feet high. The volcano of Skye was not smaller than that of Mull, and those of Rum, Ardnamurchan, and St. Kilda, though smaller, were mountains of great extent and elevation. The granites of Arran, and, in Ireland, those of the Mourne mountains and the basalts of Antrim, are also referred to the same age. Thus, in the Meiocene age, along a line of 400 miles from north to south in the British area, there rose a chain of lofty and active volcanoes, on a scale comparable to those of the Andes, overwhelming from time to time with their lava and ashes the Meiocene forests in their vicinity. This line of ancient volcanoes is continued northwards into the Färoes, Iceland, and Greenland.
Denudation since the Meiocene Age.
The present state of these volcanoes affords us a means of measuring the destruction of rock in the post Meiocene times. In Fig. 7 the dotted line represents the outline of the Meiocene surface, while the actual surface is shown by the continuous line. Not only have their cones disappeared by the action of the elements, but the more solid accumulations forming their bases have been reduced to mere fragments during the untold ages which have passed away since they were active. Since they have lost more than one half of their former height, it is reasonable to suppose that similar amounts of rock have been removed from other areas in Great Britain, the greatest destruction being wrought on the flanks of the mountains, and the least on the slopes near the sea level. Under these circumstances, we could not expect that any traces of the old Meiocene land surface or river deposits should be preserved to the present day, excepting under very unusual conditions. They for the most part have been swept away, along with a flora and fauna probably as rich as that of the continent, leaving behind a few fragments preserved from destruction by the great original thickness of the deposit, or by its having been covered up by showers of ashes and streams of lava from the Meiocene volcanoes.
The Meiocene Rivers.
The rivers of Britain in the Meiocene age (Fig. 6) were probably in the position which they now occupy, although they flowed at a higher level—the only difference being that their lower courses were prolonged to the coast-line of the period. The Severn, for example, and the Dee, Mersey, and Ribble, would debouche into the Atlantic after traversing the lower grounds now submerged. The Trent and Humber, in like manner, would find their way into the south-eastern sea.[10] Some of the Irish lakes also—such as Lough Neagh—were lakes then. In Devonshire the small lake of Bovey reflected on its still surface the luxuriant forests by which it was surrounded.
The British Meiocene Forests.
The Meiocene forests of Britain, preserved in the deposits of ancient lakes, or buried under volcanic ashes and lavas, occur merely in a few isolated spots in Devonshire, the Scotch isles, and in Ireland.
The lignites of Bovey Tracey,[11] to the south-east of Dartmoor, and their associated sands and clays, were formed in a lake at least fifty fathoms deep, and spread over an area of about twenty-four square miles, fed by the rivers Teign and Bovey, which did not then unite as they do now. In other respects, the leading features of the district were then nearly as they are now, and the heights of Dartmoor and the neighbouring hills commanded the lake very much as they stand at present over the plains of Bovey. The woods then growing on the sides of the lake and on the banks of the rivers were to a large extent composed of a huge conifer (Sequoia Couttsiæ), analogous to the mammoth tree (Sequoia (Wellingtonia) gigantea) of California, and in general appearance identical; its leaves, however, were shorter, and its cones smaller. Cinnamon trees (Cinnamomum lanceolatum and C Scheuchzeri) were abundant, and an evergreen oak (Quercus Lyelli), somewhat like those now living in Mexico. There were evergreen figs also, and custard apples (Anona), and a species belonging to the genus Gardenia. Vines leapt from tree to tree, and the prickly rattan-palm (Palmacites dæmonorops) was to be seen among the dark green foliage of the Dryandroides, which calls to mind the banksias of Australia. Gum trees were also there; and the spindle trees, now found in the warmer regions of Europe, North America, Asia, and Africa, are represented by a species of Celastrus. In the shade throve numerous ferns, one of which (Pecopteris lignitum) seems to have formed "trees of imposing grandeur," and the undergrowth was largely composed of various species of the North American genus Nyssa. On the margin of the lake clusters of water-lilies raised their beautiful blossoms and dark-green leaves, shedding the highly-ornamented seeds which lie buried in the sand and mud formed by the water.
This flora is identified by Professor Heer with that of the lower Meiocenes of France and Switzerland.
Meiocene Flora of the Hebrides and Ireland.
A flora similar to that of Bovey Tracey occurs in the island of Mull under lava and volcanic ash, consisting of the red wood (Sequoia Langsdorfii), hazel (Corylus grossidentatus) , plane, and several other trees. It is also met with in the lignites under the basalts of Antrim. A fir tree (Pinus Plutonis) closely allied to the cluster pine, a cypress, and a gum tree have been identified from this deposit by Mr. Baily, and some of the leaves strongly resemble the buckthorn, beech, and an evergreen oak. In another place in Ireland, near Shane's Castle, Lough Neagh, the ash-beds have yielded the red wood and a species of plane (Platanus aceroides).[12]
Meiocene Flora on the Continent.
The vegetation hitherto recorded in the British Isles is but an insignificant fragment of the extraordinary flora revealed by the labours of Professor Heer and others on the mainland of Europe. The Meiocene forests of France, Germany, Switzerland, and Italy comprised forms now met with only in widely remote parts of the earth, and are of singular interest because of their testimony, not merely as to climate, but also to a closer geographical relation between Europe, Asia, and America in the Meiocene age than at the present time.
The number of European species is estimated by Professor Heer at about 3000, of which 920 have been collected in Switzerland. The cycads, so abundant in the Secondary period, are represented by two species, while of the cypresses one (Glyptostrobus) is to be met with in Eastern Asia; another (Taxodium distichum), found in the fossil state in Spitzbergen, Alaska, and Italy, is that which gives its name to the cypress swamps of the Southern States and of South America. The Libocedrus is now only to be found in California, Chili, and Australia, and the Widdringtonia in South Africa and Madagascar, all being exotic and tropical or sub-tropical. The mammoth tree and red wood tree of California lived in the Meiocene forests from the Mediterranean to the Arctic circle. In Switzerland a Puya, like that of Chili, represents the exotic pine-apple family, and a large-leaved ginger contributed greatly to the tropical character of the foliage.
The Meiocene palms were represented in the Swiss forests by at least eleven species, which may be grouped into fan-palms (see Fig. 8), with the leaflets all diverging from the tip of the leaf-stalks, and the feather-palms, in which they spring right and left from the foot-stalk. To the former belong the dwarf fan-palm, the Sabal major, which then lived in central Italy and northern Germany as far as 51° N., bearing a strong resemblance to the shadow-palm of the West Indies. A second agrees with the swamp palmetto of the Southern States in its small leaves, while the leaves of a third are estimated by Professor Heer to have been no less than six or seven feet broad; they sprang from a lofty trunk, and must have formed a prominent feature in the landscape. Of the feather-palms the Phoenicites may be compared to the Piassava of Brazil, and had leaves two feet long, while the Manicaria possessed great undivided erect leaves springing from a lofty trunk.
The Meiocene poplars of Switzerland belong to the group of aspens, black poplars, balsam poplars, and leather poplars, with evergreen leaves, the first two of which are met with in Europe, Asia, and America, the third in America and Asia, while the fourth is now only found in Asia. The hornbeam and the hazel were present, and of the oak no less than thirty-five species have been determined, for the most part evergreens of American or Mediterranean types. There were also lindens, maples, hollies, walnuts, ilices, cherry, plum, and almond trees, mimosas and acacias, alders, birches, and other trees familiar to our eyes. The genus Planera is the most interesting Meiocene representative of the elm family, since it ranges from central Italy as far as Greenland, and from the canton of Vaud in the west to Tokay, in Hungary, on the east. It probably formed woods on the low damp grounds close to the rivers. At the present time it is found in Crete, in Asia, south of the Caucasus, and in North America. Myrtles formed dense copses, for the most part evergreen; and the fig trees, represented by seventeen species in the Swiss Meiocenes, belong to Indian and American types, one of which is remarkably like the Indiarubber tree (Ficus elastica), and another like the bread-fruit. It is a curious fact that the present European fig-tree (Ficus carica) is absent from this flora. The laurels were more abundant than the figs in Switzerland, the two most important species being the camphor tree and Scheuchzer's cinnamon tree. These range throughout the Meiocene strata, and are found fossil in Italy, Germany, France, and Britain. The former is a native of southern Asia, but it thrives also in Sicily and Madeira, while the latter resembles a Japanese laurel.
The camphors, cinnamons, and laurels were large evergreen forest trees; the sassafras was probably a shrub or small tree. A species of sandal-wood tree, belonging to a well-marked Australian genus, Leptomaria, and the Australian Proteaceous genera, Hakea, Dryandra, Banksia, and Grevillia, have also been met with. Of the climbers, the convolvulus family is represented by the Indian genus Porana, while Bignonias, now found only in the sub-tropical and torrid zones, wound round the trees. There were also small-leaved ivies, and vines allied to the American fox-grape; and among the climbing plants several species of Sarsaparilla. Magnolias, tulip trees, and planes ranged in the Meiocene age from Italy to Iceland, and the gum tree from Italy to Britain.
The general conclusions drawn by Professor Heer as to the Swiss Meiocene species are as follows:—"Of the species most nearly resembling the Swiss Meiocene species, 83 live in the northern United States and 103 in the southern United States, 40 in tropical America, 6 in Chili, 58 in central Europe, 79 in the Mediterranean zone, 23 in the temperate, 45 in the warm, and 40 in the torrid zone of Asia, 25 in the Atlantic islands, 26 in Africa, and 21 in Australia.
"These numbers show that in the Meiocene period Switzerland was inhabited by types of plants which are now scattered over all parts of the world, but that most of them correspond to American species. Europe only stands in the second rank, Asia in the third, Africa in the fourth, and Australia in the fifth. Most of the analogous species of Europe are found in the Mediterranean countries, in America, in the southern United States (Louisiana, Florida, Georgia, and Carolina), and also in California, in the Caucasian region of Asia, in Japan, in Asia Minor, in Madeira, and the Canary Islands. Swiss Meiocene species are also represented in the torrid zone of Asia, in the Sunda Islands, and in tropical America.
"When the mass of vegetation is considered, which was the special characteristic of Switzerland in Meiocene times, greatly increased prominence is given to the Japanese types by the abundance of camphor trees and Glyptostrobi; to the Atlantic element by the laurels; to the American types by the numerous evergreen oaks, maples, poplars, planes, liquidambars, Rohiniæ, Sequoiæ, Taxodia, and ternate-leaved pines; and to the types of Asia Minor by the Planeræ and a species of poplar (Populus mutabilis). The greatest number and the most important of the types of the Swiss Meiocene flora belong, therefore, to a belt lying between the isothermal lines of 59° and 77° Fahr. (15° to 25° Cent.), and in this zone America is now the region mostly correspondent to the natural character of the Swiss Meiocene land."[13]
Lower Meiocene Mammals.
The mammals inhabiting the Meiocene forests of Europe must be considered in three divisions, as they appeared successively in time. The first group of mammals presents, as may be expected, an assemblage of forms, some of which are new, while others are survivals from the upper Eocene. Among the latter are the Xiphodon and Kainothere, the Anchithere and the Paloplothere, as well as the Opossum and carnivorous Hyænodon. The two animals most characteristic of this stage are the hog-like Hyopotamus, and the remarkable creature the Anthracotherium, possessing back teeth like the hog, but front teeth (premolars, canines, and incisors) as well adapted for piercing and dividing flesh as in any of the true carnivores. The living genera were represented by the following animals. Rhinoceroses of small size, some without horns, and tapirs, lived in the forests; there were squirrels and dormice, hedgehogs, shrews, musk-shrews, together with beasts of prey belonging to the genera Mustela and Viverra. There were also moles burrowing in the ground. There were no true hogs nor representatives of the family of elephants, and among a large and varied group of animals representing the deer and the antelope there were none bearing antlers or horns.
The most important fact to be remarked in the mammalia of Europe at this period is that the opossums were still lingering in the forests, and that the marsupial ancestry of the Carnivores still asserted itself in the singular combination of characters offered by the Hyænodon. Here we bid farewell to the European marsupials, and none of their characters have been observed in any placental mammal living in the Old World in any subsequent age.[14]
Lower Meiocene Birds.
We are indebted to Professor A. Milne-Edwards[15] for an admirable account of the birds inhabiting the shores of the lower Meiocene lake in the district of the Allier at St. Gerand-le-Puy, Varennes, and other localities. He has described sixty-six species belonging to groups, some of which are no longer found in the region north of the Mediterranean. Parroquets and trogons inhabited the woods; birds-nest-swifts built their nests in hollows of the rocks, after the fashion of those which one finds at the present time in the Indian Archipelago; a secretary bird, closely allied to that of the Cape of Good Hope, hunted in the plains the serpents and reptiles which then, as now, must have formed its usual food; and eagles swooped down on their prey. Large marabouts, cranes, flamingoes, and strange extinct birds, Palælodus, allied to the flamingoes and the ordinary waders and ibises, haunted the borders of the streams. Pelicans floated in the lakes, while sand-grouse and numerous gallinaceous birds contributed to give to this ornithological fauna a most striking character, which reminds us of those pictures which Livingstone has put before us of lakes in southern Africa. The greater part of these birds appear to have nested in the Allier, if they did not inhabit the district throughout the whole year.
Mid Meiocene Mammalia.
Sabal major (Ung.)
Manicaria formosa (Heer).
Flabellaria Ruminiana (Heer).
|
Ape. |
Mastodon. |
Fig. 8.— Mid Meiocene Mammalia.
their antlers and horns being very small, were to be seen in the plains. One species of deer (Dicroceros elegans) was closely allied to the Muntjak[17] (Fig. 8)[18] of eastern Asia, and in some others the antlers were persistent throughout life. In the rivers beavers made their dams, and otters pursued their finny prey. Among the more important extinct genera (Fig. 8) then living, were two large animals resembling in habits and general appearance the elephants. One, the Deinotherium, was remarkable for two large tusks curving downwards in the lower jaw; while the other, the Mastodon, possessed tusks in both upper and lower jaws, and teeth of a much coarser pattern than those of the elephants. Rhinoceroses also, one with a very feeble horn, and the other hornless, fed on the luxuriant vegetation; and an extinct kind of gigantic ant-eater, Macrotherium, allied to the Orycteropus of southern Africa (Fig. 8), dug into the ant-hills with his powerful claws, and preyed upon the Termites. We meet also with Anchitheres for the last time. These herbivores were kept in check by numerous carnivores, of which the most important was the great sabre-toothed lion, Machairodus.
Apes in the Mid Meiocene Forests.
The most important animals to be noted in the mid Eocene forests of France, Switzerland, Germany, and Italy, are certain large apes, identified by Dr. Rütimeyer with the genus Hylobates, one of the more highly developed of the Quadrumana. It is considered, however, by Professor Gervais[19] and Dr. Forsyth Major to indicate an extinct genus, Pliopithecus, allied to the anthropoid apes, and differing in the form and proportions of its teeth from that of the true Gibbons.
In Fig. 8 the latter animal is taken to indicate the probable appearance of the fossil. A second ape, Dryopithecus Fontani,[20] found in association with oak-trunks at Saint Gaudens, Haute Garonne, is considered by Prof. Lartet to be one of the anthropoid apes, rivalling man in size, and by Prof. Owen[21] to be allied to the Pliopithecus and living gibbons. A third ape, found at Steinheim in Wurtemberg, is described by Prof. Fraas[22] as a species of Colobus (C. grandævus); while a fourth, Oreopithecus, found in the lignites of Monte Bamboli, is stated by Prof. Gervais[23] to be allied to the anthropoid apes, the macaques and the baboons. {{dhr}]
Mid Meiocene Birds.
The mid Meiocene birds identified by Prof. Milne-Edwards belong principally to living families, but do not present us with any living species. There is a parroquet more slender than that of the Allier, and large gallinaceous birds about the size of peacocks frequented the borders of the lakes. The shores of the sea in which the marine faluns of the Loire were deposited, were inhabited by cormorants, geese, herons, and pheasants.[24]
Land Mammalia and Birds of Upper Meiocenes.
The third well-marked invasion of Meiocene Europe by the mammalia is that represented by the remains found in Germany at Eppelsheim, in Hungary at Baltavar, in France at Mont Léberon, in Spain at Concud, and in Greece at Pikermi. Numerous antelopes and two closely allied species of gazelle spread in vast troops over the plains of Hungary, Spain, Southern France, and the shores of the Mediterranean. A large wild hog with small canines, and two sorts of rhinoceros, horned and hornless, a tapir, gigantic elephant-like creatures, the Deinotherium, and the Mastodon, roamed through the forests and bathed in the rivers, and fell a prey to the great sabre-toothed feline Machairodus. All these genera, it will be remembered, lived also in the forests of the mid Meiocene age in France, Switzerland, and Italy. Great herds of Hipparions, animals resembling small asses or quaggas, intermediate in structure between the Anchithere and the horse, wandered over the whole of Europe, the greater part of Asia and of North America. A small deer with bifurcating antlers, resembling the Muntjak of tropical Asia, ranged over France and Germany, while a second, with small upright antlers of a shape unlike any living species (Fig. 9), flourished in France and probably also in Spain.
Fig. 9.—Cervus Matheroni, Gervais, Mont Léberon, 13.
The plains of Pikermi, then stretching southwards from the rocky mountains of Attica far into the area now covered by the Mediterranean, supported countless troops of antelopes, varying in size and form, and, for the most part, allied to those of Africa; one, the Helladotherium, was of large size and allied to the giraffe; this last animal was also present. Numerous apes (Mesopithecus) inhabited the woods, intermediate in character between the Semnopithecus on the one hand, and the Macacus or Barbary ape on the other, being related to the one in the form of its head, and to the other in the length of its limbs. A large ape also has been met with at Eppelsheim. Thus in the upper Meiocene age the range of the Quadrumana extended from the shores of the Mediterranean, at least as far to the north as 49° 43' north latitude, or 14° farther north beyond the present northern limit of the old world apes.
The Edentata (sloths, ant-eaters, etc.) also were represented by two forms which survived from the middle Meiocenes, lived in France and Germany; the Macrotherium, or gigantic ant-eater; and the Ancylotherium, allied to the rhinoceros and mastodon as well as to the Pangolins of Asia and Africa. Like the living Pangolin, the latter probably fed upon insects, and more especially ants and termites, which Professor Heer has shown to have abounded in Meiocene Switzerland.
Three kinds of birds inhabited the Mediterranean district in the neighbourhood of Attica, a pheasant (Phasianus Archaici) larger than the common species, a small fowl (Gallus æsculapii) , and a wader (Grus Pentelici).
Meiocene Geography on the Continent.
Great geographical changes took place in the Meiocene age on the continent of Europe. In the lower Meiocene large tracts of land were submerged in France, Belgium, and Italy. Then followed a period of elevation above the sea-level, during which there were great lakes in Auvergne and Switzerland, in which the lower freshwater "molasse" were deposited. Then followed a second period of depression below the sea-level, which reduced the continent to the condition of an archipelago. The waters of the Mediterranean flowed northwards past Berne to join the sea, then covering the basin of the Danube. This mid Meiocene sea afterwards gradually became shallower, and the freshwater lakes of the lower Meiocene are again repeated in Switzerland and in France in the upper Meiocene age.
Auvergne was one of the centres of volcanic activity, and the Meiocene lakes were frequently invaded by streams of lava and clouds of ashes. In Switzerland also the formation of great lakes of upper Meiocene age was accompanied by the development of volcanoes, at Oeningen.[25]
The central axis of the Alpine chain occupied its present position, and may have been as high or higher than it now is. The denudation, by which it has suffered in the long lapse of ages since the Meiocene times, has been compensated by the amount of elevation by which the Meiocene strata of the Tongrian zone have been lifted up no less than 10,940 feet above the sea in the Dent du Midi., Those of the Helvetian zone have been elevated 2470 feet at Lausanne, and 2800 at Berne.[26]
The same remarks apply also to the Pyrenees, although their history has not been made out with the same accuracy as that of the Alpine chain.
The Meiocene Climate.
The testimony as to climate offered by the Meiocene vegetation is clear and decisive. The numerous palms could only have flourished under a warm and equable climate, and the flora as a whole is now only to be found in sub-tropical regions, where the winters are very mild. In the vast lapse of time, however, represented by the Meiocene strata in Switzerland, a gradual lowering of temperature is marked by changes in the vegetation. In the lower Meiocene, or Aquitanian stage, evergreen trees and shrubs constitute nearly three-quarters of the whole forest, while in the upper Meiocene they divide the flora with the deciduous trees. Palms, fig-trees, and fine-leaved acacias abound in the lower, while in the upper strata they are to a great extent replaced by maples and poplars. The palms are found throughout, but are more rare in the upper strata. The greatest change, as we might expect, occurs at the time when the sea rolled over part of Switzerland in the middle, or Helvetian stage.
The elaborate investigations of Professor Heer show that the climate of middle Europe was in the lower Meiocene stage similar to that now prevailing in Louisiana, the Canaries, North Africa, and South China, with a mean annual temperature of from 68° to 69⋅8° Fahr.; while that of the Upper Meiocenes resembled that of Madeira, Malaga, Southern Sicily, Southern Japan, and New Georgia, with a mean annual temperature of 64⋅4°, 66⋅2° Fahr.
While the climate was warm in the region south of the Baltic, it was temperate in Iceland, where the flora consists of species capable of living under temperate conditions. The same remark holds good with regard to the Meiocene plants of Spitzbergen, in which we do not find any tree or shrub with evergreen foliage. It also holds good for that of the western coast of North Greenland, in 70° north latitude, where magnolias, chestnuts, oaks, planes, and vines, indicate "climate analogous to that now characteristic of the lake of Geneva."
These conclusions as to the nature of the climate[27] in Meiocene Europe are confirmed by the distribution of animal life. Among the insects of Switzerland we find the white ants, or termites, now peculiar to hot countries, dragonflies of South African type, land crabs, also peculiar to the tropics, and among the mollusca inhabiting the rivers and lakes, the exotic genus Melania. The insect fauna, however, of Oeningen contains very many forms now living in Switzerland and in southern Europe, and is, on the whole, as Professor Heer observes, more of Mediterranean than of tropical and American stamp.
The amphibians and the reptiles belong to genera now widely scattered, and some peculiar to warm countries. The gigantic Meiocene salamander (Andrias Scheuchzeri) , four feet long, is allied to those of southern Japan and America; a gigantic frog is closely allied to the horned frog of Brazil; a crocodile to that now found in the Nile; an alligator-tortoise, about three feet long, to that of the genus now abundant in the warm rivers of the Southern States; and a river tortoise (Emys) to those of the rivers of India and Africa.
The secretary birds, ibises, flamingoes, parroquets, and marabouts present us with an assemblage of birds now found only in warm regions; while the giraffes, antelopes, deer, and rhinoceroses of middle and southern Europe are forms analogous to those now restricted to tropical Africa and southern Asia. Monkeys of various sorts extended from the Mediterranean as far north as Eppelsheim, and fed upon the figs and bread-fruits, walnuts, almonds, dates, rice, and millet, as well as on the acorns, then growing in those regions.
No Evidence of a Glacial Period in the Meiocene Age.
It is believed by some authorities[28] that during the long ages of the Meiocene period there was a glacial climate in Europe, "as severe as, if not more excessive than, the intensest severity of climate experienced during the last glacial epoch;" or, in other words, that there was as great a lowering of the temperature as that by which great tracts of land were covered with ice and snow in the Pleistocene age. This conclusion is founded upon the discovery of angular blocks of stone in the upper Meiocene strata of the Superga Hill, near Turin, which have been conveyed some twenty miles away from the Alpine localities in which similar rocks are seen in situ. They are angular and indistinguishable from the erratic blocks of the district, and are believed by Sir Charles Lyell and Professor Gastaldi to have been transported to their present positions by ice.[29] It seems to me that these blocks do not prove a severe climate in any place except where the ice in question has been produced, which may have been on the tops of lofty mountains, like those of the Andes, which send glaciers down to the sea in Eyre Sound, Patagonia, in the latitude of Paris. They tell us no more of the Meiocene climate of Europe than the glaciers at present in New Zealand[30] tell us of a climate which is sufficiently mild to allow of the growth of tree ferns and areka palms. It is impossible that a great climatal change could have taken place in the Meiocene age affecting Europe generally, without leaving its mark in the flora and in the fauna. One severe winter would have destroyed the evergreen forests, and the exotic plants and animals would disappear and be replaced by others capable of flourishing under the new conditions. The blocks of stone may have been carried down by glaciers from the Alpine chain, then lifted high up above the sea into the icy temperature which is to be met with everywhere on the earth at great altitudes. They may be referred to that glacial climate which is above our head even at the equator, rather than to glacial conditions extending down to the sea-level in Italy, in a period when the climate of middle and northern Europe was warmer than it is now—a period, moreover, in which, if Professor Heer's views be accepted, even in the Arctic Regions, it was sufficiently mild to allow the spruces, elms, and hazels, the hemlocks and swamp cypresses to flourish in Grinnell Land, almost as far north as latitude 82°,[31] and the vine, walnut, tulip tree, and mammoth tree to grow luxuriantly in Iceland.
No Proof of Man in Europe in the Meiocene Age.
Was man an inhabitant of Europe in the Meiocene age? Did he wander through the evergreen forests and hunt the deer, antelopes, and hogs, the Hipparions, Mastodons, and Deinotheres, then so numerous? The climate was favourable, and the food, animal and vegetable, was most abundant. The representatives of the higher apes were present in Germany, Switzerland, France, Italy, and Greece, and all the conditions were satisfied which have been put forward by Dr. Falconer and Sir John Lubbock as necessary to that primeval garden of Eden in which the first traces of man were to be sought. Meiocene Europe was fitted to be the birthplace of man, in its warm climate and in the abundance of food. There is, however, one most important consideration which renders it highly improbable that man was then living in any part of the world. No living species of land mammal has been met with in the Meiocene fauna. Man, the most highly specialised of all creatures, had no place in a fauna which is conspicuous by the absence of all the mammalia now associated with him.
Were any man-like animal living in the Meiocene age, he might reasonably be expected to be not man but intermediate between man and something else, and to bear the same relation to ourselves as the Meiocene apes, such as the Mesopithecus, bear to those now living, such as the Semnopithecus. If, however, we accept the evidence advanced in favour of Meiocene man, it is incredible that he alone of all the mammalia living in those times in Europe should not have perished, or have changed into some other form in the long lapse of ages during which many Meiocene genera and all the Meiocene species have become extinct. Those who believe in the doctrine of evolution will see the full force of this argument against the presence of man in the Meiocene fauna, not merely of Europe but of the whole world.
On the other hand, it is maintained by very high authorities—Dr. Hamy,[32] M. de Mortillet,[33] and others—that man inhabited France as early as the middle of the Meiocene age. This conclusion is founded partly on the splinters of flint[34] found in the mid Meiocene strata at Thenay by the Abbé Bourgeois,[35] and on a notched fragment of a rib of an extinct kind of manatee (Halitherium) found at Pouancé by M. Delaunay. The data seem to me insufficient to establish the fact that man was a contemporary of the Deinothere and other members of the mid Meiocene fauna. Is it possible for the flints in question, which are very different from the Palæolithic implements of the caves and river deposits, to have been chipped or the bone to have been notched without the intervention of man? If we cannot assert the impossibility, we cannot say that these marks prove that man was living in this remote age in the earth's history. If they be artificial, then I would suggest that they were made by one of the higher apes then living in France rather than by man. As the evidence stands at present, we have no satisfactory proof either of the existence of man in the Meiocene or of any creature nearer akin to him than the anthropomorphous apes. These[36] views agree with those recently published by Professor Gaudry,[37] who suggests that the chipped flints and the cut rib may have been the work of the Dryopithecus, or the great anthropoid ape, then living in France. I am, however, not aware that any of the present apes are in the habit of making stone implements or of cutting bones, although they use stones for cracking nuts.[38]
From the preceding pages the reader will have realised how different Europe of the Meiocene age was from the Europe of to-day; that the climate was much warmer, and that it was connected with Greenland, Spitzbergen, and North America; and that on the land so constituted, during the Eocene and Meiocene ages, luxuriant forests extended northwards far into the Polar regions. He will also have realised that, in the European part of this vast forest-covered continent, there was not one living species of mammal to be seen in the strange and varied fauna to herald the order of things that was to be, although there were many familiar trees and some reptiles, such as the alligator and crocodile. When all this is taken into account, it will be seen how improbable, nay, how impossible, it is that man, as we know him now, the highest and most specialised of all created forms, should have had a place in the Meiocene world. The evolution of the animal kingdom, recorded in the rocks, had at this time advanced as far as, but no farther than, the Quadrumana, and it seems to me not improbable that some of the extinct higher apes may have possessed qualities not now found in living members of their order.
- ↑ Mr. Starkie Gardner believes them to be of upper Eocene age.
- ↑ Paléont. Française, 1859, p. 190.
- ↑ Sequoia Couttsiæ, Nelumbium (Nymphæa) doris, Andromeda reticalata, Carpolithes Websteri.
- ↑ Chelydra Murchisoni, Bell. The representative species inhabits the rivers and lakes of the United States, from New York to Florida, and is a rapacious animal, living on fishes, amphibia, and young birds.
- ↑ Latonia Seyfriedi, Meyer. According to Heer, allied to Ceratophrys cornuta.
- ↑ The genus Naupactus and others. See Heer, Primeval World of Switzerland, ii. c. i.
- ↑ Climat et la Végétation du Pays Tertiaire, transl. Gaudin; 4to. See also Lyell, Student's Elements, 1865, c. xvi.
- ↑ Quart. Jour. Geol. Soc. Lond. xxx. p. 259.
- ↑ Fig. 7 is taken from Professor Judd's Section, Quart. Jour. Geol. Soc. Lond. xxx. p. 259, Pl. xxiii.
- ↑ Ramsay (Physical Geology and Geography of Great Britain, p. 217, et seq.) believes that the lower part of the valley of the Severn and the whole of the Thames valley are post-Meiocene.
- ↑ The Lignites of Bovey Tracey, by William Pengelly, F.R.S., and Dr. Heer. Phil. Trans. 1862. 4to, 1863, p. 18.
- ↑ Quart. Journ. Geol. Soc. Lond. (1853), vii. 103; (1869), xxv. 357; (1870), xxvi. 162.
- ↑ Heer's Primeval World of Switzerland. Transl. Heywood, vol. i, pp. 370, 371.
- ↑ For details of lower Meiocene Species see Appendix II. A.
- ↑ Oiseaux Fossiles, 4to.
- ↑ See Appendix II. B.
- ↑ Procervulus Aurelianensis, Gaudry (Les Enchainements, 87, from Thenay (Loir-et-Cher). The antlers are without a burr.
- ↑ The Gibbon, the Muntjak, and the Orycteropus are taken to represent the apes, the deer, and the edentates in Fig. 8.
- ↑ Lartet, Notice sur la Colline de Sansan, Auch, 1851. Gervais, Zool. et Pal. Francaises, p. 8. See Forsyth Major, Actes de la Société Italienne des Sc. Nat. xv. 1872. Rütimeyer, quoted by Heer, Le Monde Primatif en Suisse.
- ↑ Lartet, Comptes Rendus, xliii. 1856. The late development of the wisdom tooth or last molar, considered by Professor Lartet to be a character common to this animal and man, is also met with, as Dr. Forsyth Major observes, in the Macacus rhesus. It has not, therefore, the importance which is attached to it both by Professor Lartet and Sir Charles Lyell (Student's Elements, p. 196). See also Professor Gaudry's interesting analysis of the characters of this jaw, Sur les Enchainements, p. 237 et seq.
- ↑ Owen, Proceed. Zool. Lond. xxvi. 1859, p. 18.
- ↑ Fraas, Die Fauna von Steinheim Wurtemberg Nature. Jahreshefte, xxvi. 1870, p. 145.
- ↑ Zool. et Pal. 2d ser. 4to, p. 9.
- ↑ Ann. des. Sc. Nat. 5e sér. Zool. et Paléont. lxvi. p. 1.
- ↑ Heer, Primeval World of Switzerland, i. p. 303.
- ↑ Heer, op. cit.
- ↑ Heer, Primeval World of Switzerland, ii. 147. We must note that the Polar vegetation taken by Heer to be Meiocene is considered by Dawson and Starkie Gardner, Eocene. This question is discussed in the second chapter of this work.
- ↑ See Croll, Climate and Time, pp. 306, 357.
- ↑ Lyell, Principles, i. p. 206, 10th edit.
- ↑ Lyell, Principles, i. 211.
- ↑ See Heer, Quart. Journ. Geol. Soc. Lond. xxxiv, p. 66, and Flora Arctica.
- ↑ Paléontologie Humaine, par M. le Dr. Hamy, p. 45 seq., 8vo. Quart. Journ. Science, 1879.
- ↑ Revue Prehistorique, 1879, p. 117.
- ↑ A collection of these flints is to be seen in the museum at St. Germain, some of which appeared to me, in 1876, non-artificial, while others had evidently, from the state of their surfaces, been exposed to the atmosphere for a considerable time. Those figured by Professor Gaudry (Les Enchainements, p, 239) are, to all appearance, artificial.
- ↑ Congres Intern. Préhist. Archéol., Paris vol. p. 67 et seq.; Brussels vol. p. 81 et seq.
- ↑ This was written in September 1877, and used in the Owen's College Lectures of November 1877.
- ↑ Les Enchainements, p. 241.
- ↑ Even if the existing apes do not now make stone implements or cut bones, it does not follow that the extinct apes were equally ignorant, because some extinct animals are known to have been more highly organised than any of the living members of their class. The Secondary reptiles possessed attributes not shared by their degenerate Tertiary successors. The Deinosaurs and Theriodonts had structural peculiarities now only met with in the birds and the mammalia.