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bouring shallows or coast-line, forming beds of gravel which form the first covering of the chalk, wherever it has received other older tertiary deposits. The beds of nummulites and miliolites contemporaneous with those containing the Sheppey plants and the Paris quadrupeds, seem to indicate a deep sea at no great distance, and prove that there were frequent alternations from the deep sea to a coast-line, perhaps the result of disturbances acting in the direction already alluded to.
The shores of the islands or of the tract of main land then existing were apparently low and swampy, rivers bringing down mud in what is now the south-east of England and the neighbourhood of Brussels, but extensive calcareous beds near Paris. Deep inlets of the sea, estuaries, and the shifting mouths of a river, were also affected by numerous alterations of level not sufficient to destroy, but powerful enough to modify the animal and vegetable species then existing; and these movements were continued for a long time. The seas were tenanted by sharks, gigantic rays, and many other fishes of warm latitudes, and abounded also with large carnivorous mollusca, capable of living either in fresh or brackish water. The shelving land was clothed with rich tropical vegetation to the water's edge, presenting to view the palm and the cocoa-nut, besides many of those trees which now lend a charm to the Spice Islands of the Indian seas. All these abounded also with indications of animal life.
The large rivers were peopled with crocodiles; turtles and tortoises floated upon them; and these tenants of the water, strange and varied as they
were, and unlike the present inhabitants of the district, were not without resemblance to many species still met with on the earth.
The interior of the land, of which the surrounding waters were thus peopled, was no less remarkable, and exhibited appearances equally instructive. Troops of monkeys might be seen skipping lightly from branch to branch in the various trees, or heard mowing and chattering and howling in the deep recesses of the forest. Of the birds, some clothed in plumage of almost tropical brilliancy, were busy in the forests, while others, such as the vulture, hovered over the spots where death had been busy. Gigantic serpents might have been seen insidiously watching their prey. Other serpents in gaudy dress were darting upon the smaller quadrupeds and birds, and insects glittered brightly in the sun. All these indications of life and activity existed, and that, too, not far distant from the spots on which are placed the two most important cities in the world. But this happened not only before our island was visited by its earliest human discoverer, but long before man had been introduced on the earth.
Not less strange, however, than those already alluded to, were the other inhabitants. With the monkeys were associated small opossums, squirrels, a racoon, and other animals at that time the tenants of the forest. Several of the smaller Carnivora prowled about preying upon these, and amongst whom, a species of fox and a wolf show, that, as there was a large supply of animal food, so there were other animals to avail themselves of the supply. But in all this one thing is remarkable; it is the almost total
absence of the tribe of ruminants. None of those which are so useful and almost necessary to man were then to be seen. The deer tribe and the goat, the sheep, the ox, the camel, all are wanting, and their place was filled by various representatives belonging to the tribe of which the hog, the horse, the rhinoceros, and the elephant, are the present types. These, indeed, were abundant and varied enough, both in their dimensions, their appearance, and their habits. Some swam in the water; some tripped lightly and elegantly on the borders of the marshes; others, constantly on the alert, ran like the wind at the slightest approach of danger, or were watching that they might escape by flight or concealment the fate that attended them. Everything was thus perfectly adapted to animal wants and necessities, but no preparation was yet made for man. Quadrupeds had taken the place once held by reptiles, and include herbivorous as well as carnivorous forms, and so far an advance seems to be indicated, but the destructive races still preponderated in point of numbers and importance.
Such seems to have been the condition of things at this early tertiary period, as far as is made known by geological investigations in Europe, and thus grand seems to have been the first development of the higher types of animal existence, if, indeed, our ignorance of more ancient tracts of widely extended land may not have led us falsely to the conclusion that true mammalian quadrupeds were only abundant during the last epoch of the earth's history.
THE CONDITION OF EUROPE AFTER THE OLDER TERTIARY BEDS HAD BEEN DEPOSITED, BUT PREVIOUS TO THE HISTORIC PERIOD.
THE great series of modifications of the surface affecting Europe, of which the commencement has been described in the last chapter, continued at intervals through a very long period, marked by successive changes in animal and vegetable organization, until at length we reach to the existing creation. Looking, however, at the most recent conclusions of palæontologists concerning tertiary formations generally in the old continents, there does not appear any probability of a true subdivision of those beds into distinct periods, nor does there seem any proof of more than a mere local grouping of the various parts. The whole of the tertiary geology in Europe may certainly be regarded as continuous; and perhaps it would be found that all the other epochs were in the same way really unbroken, if we were in possession of materials enabling us to observe with accuracy the mutual bearing and influence of each part upon the whole development throughout all time.
We left off in the last chapter with an account of deposits chiefly in the vicinity of London and Paris, but reaching also on the one side to the capital of Belgium, and on the other to the south flanks of a
portion of the Alps, and the eastern part of the Mediterranean. There can be little question that throughout the whole of Europe the general change of level the commencement of which is thus marked was such as to produce elevation on a grand scale, but it was long before this elevation was sufficient to raise above the waters the great plains of our continent, or those districts watered by its principal rivers. These, indeed, were the recipients of the great mass of the deposits then going on; and it is not unlikely that the very fact of reiterated changes of level may have rendered the amount of material thus removed very considerable.
The great valleys of the Loire and the Garonne in France; the tract between the High Alps and the Jura mountains in Switzerland; the tract north of the Alps extending eastwards in the present valley of the Danube towards Turkey, and as far as Hungary, and then northwards into Poland; the tract, also, north of the Alps extending in the Rhine valley as far as Mayence, and occupying a breadth of many leagues; the eastern coast of England, the western coast of the Spanish peninsula, and the south of France, all these districts are marked by deposits, for the most part more recent than the London and Paris beds, but more ancient than the great south Italian series, and distinctly separated from the cavern and gravel deposits, which appear to be among the newest of the geological formations in what is now called Europe. The more remarkable characteristics of this intermediate period, so far as fossils are concerned, must be sought for in the strata of the Rhine valley, where we find some remarkable and