To give the reader some idea of the formation, first come the limestones and lower marls, which contain fine lignite or wood-coal produced from vegetable matter buried in moist earth, and excluded from all access of air, a material which is worked in some parts of the south of France as actively as a coal-mine. In these lignites _Anodon_ and other fresh-water sh.e.l.ls are found.

From the base of Sainte-Victoire to the other side of Aix, we trace a conglomerate characterised by its red colour, but which dies away in its prolongation westward. This conglomerate contains land-snails (_Helix_) of various sizes, mixed with fresh-water sh.e.l.ls. Upon this conglomerate, comprising therein the marls, rests a thick deposit of limestone with the gypsum of Aix and Manosque, which is believed to correspond with that of Paris. Some of the beds are remarkably rich in sulphur. The calcareous marly laminae which accompany the gypsum of Aix contain Insects of various kinds, and Fishes resembling _Lebias cephalotes_.

Finally, the whole terminates at Manosque in a fresh series of marls and sandstones, alternating with beds of limestone with _Limnaea_ and _Planorbis_. At the base of this series are found three or four beds of lignite more inflammable than coal, which also give out a very sulphurous oil. We may form some estimate of the thickness of this last stage, if we add that, above the beds of fusible lignite, we may reckon sixty others of dry lignite, some of them capable of being very profitably worked if this part of Provence were provided with more convenient roads.

"The Nummulitic formation, with its characteristic fossils," says Lyell,[89] "plays a far more conspicuous part than any other Tertiary group in the solid framework of the earth's crust, whether in Europe, Asia, or Africa. It often attains a thickness of many thousand feet, and extends from the Alps to the Carpathians, and is in full force in the north of Africa, as, for example, in Algeria and Morocco. It has been traced from Egypt, where it was largely quarried of old for the building of the Pyramids, into Asia Minor, and across Persia, by Bagdad, to the mouth of the Indus. It occurs not only in Cutch, but in the mountain ranges which separate Scinde from Persia, and which form the pa.s.ses leading to Caboul; and it has been followed still further eastward into India, as far as eastern Bengal and the frontiers of China."

[89] Ibid., p. 305.

"When we have once arrived at the conclusion," he adds, "that the Nummulitic formation occupies a middle place in the Eocene series, we are struck with the comparatively modern date to which some of the greatest revolutions in the physical geography of Europe, Asia, and northern Africa must be referred. All the mountain chains, such as the Alps, Pyrenees, Carpathians, and Himalayas, into the composition of whose central and loftiest parts the Nummulitic strata enter bodily, could have had no existence till after the Middle Eocene period."

The Eocene strata, Professor Ramsay thinks, extended in their day _much further_ west, "because," he says, "here, at the extreme edge of the chalk escarpments, you find outlying fragments of them," from which he argues that they were originally deposited all over the Chalk as far as these points, but being formed of soft strata they were "denuded"

backwards.

The Beloptera represented in Fig. 195 are curious Belemnite-like organisms, occurring in Tertiary strata, and evidently the internal bone of a Cephalopod, having a wing-like projection or process on each side.

As a genus it holds a place intermediate between the Cuttle-fish and the Belemnite.

[Ill.u.s.tration: Fig. 157.--Cerithium telescopium.

(Living form.)]

THE MIOCENE PERIOD.

The Miocene formation is not present in England; unless we suppose, with Sir Charles Lyell, that it is represented by the Hempstead beds of the Isle of Wight.

It is on the European continent that we find the most striking characteristics of the Miocene period. In our own islands traces of it are few and far between. In the Island of Mull certain beds of shale, interstratified with basalt and volcanic ash, are described by the Duke of Argyll as of Miocene date;[90] and Miocene clay is found interstratified with bands of imperfect coal at Bovey Tracey. The vegetation which distinguished the period is a mixture of the vegetable forms peculiar to the burning climate of the present tropical Africa, with such as now grow in temperate Europe, such as Palms, Bamboos, various kinds of Laurels, Combretaceae (Terminalia), with the grand Leguminales of warm countries (as _Phaseolites_, _Erythrina_, _Bauhinia_, _Mimosites_, _Acacia_); Apocyneae a.n.a.logous to the genera of our tropical regions; a _Rubiacea_ altogether tropical (_Steinhauera_) mingle with some Maples, Walnut-trees, Beeches, Elms, Oaks, and Wych-elms, genera now confined to temperate and even cold countries.

[90] _Quarterly Journal of Geol. Soc._, vol. vii., p. 89.

Besides these, there were, during the Miocene period, mosses, mushrooms, charas, fig-trees, plane-trees, poplars, and evergreens. "During the second period of the Tertiary epoch," says Lecoq, "the Algae and marine Monocotyledons were less abundant than in the preceding age; the Ferns also diminished, the ma.s.s of Conifers were reduced, and the Palms multiplied in species. Some of those cited in the preceding period seem still to belong to this, and the magnificent _Flabellaria_, with the fine _Phnicites_, which we see now for the first time, gave animation to the landscape. Among the Conifers some new genera appear; among them we distinguish _Podocarpens_, a southern form of vegetation of the present age. Almost all the arborescent families have their representatives in the forests of this period, where for the first time types so different are united. The waters are covered with _Nymphaea Arithnaea_ (Brongniart); and with _Myriophyllites capillifolius_ (Unger); _Culmites animalis_ (Brongniart); and _C. Gpperti_ (Munster), spring up in profusion upon their banks, and the grand _Bambusinites sepultana_ throws the shadow of its long articulated stem across them. Some a.n.a.logous species occupy the banks of the great rivers of the New World; one Umbellifera is even indicated, by Unger, in the _Pimpinellites zizioides_.

Of this period date some beds of lignite resulting from the acc.u.mulation, for ages, of all these different trees. It seems that arborescent vegetation had then attained its apogee. Some _Smilacites_ interlaced like the wild vines with these grand plants, which fell on the ground where they grew, from decay; some parts of the earth, even now, exhibit these grand scenes of vegetation. They have been described by travellers who have traversed the tropical regions, where Nature often displays the utmost luxury, under the screen of clouds which does not allow the rays of the sun to reach the earth. M. D'Orbigny cites an interesting instance which is much to the point. "I have reached a zone," he says (speaking of Rio Chapura in South America), "where it rains regularly all the year round. We can scarcely perceive the rays of the sun, at intervals, through the screen of clouds which almost constantly veils it. This circ.u.mstance, added to the heat, gives an extraordinary development to the vegetation. The wild vines fall on all sides, in garlands, from the loftiest branches of trees whose summits are lost in the clouds."

The fossil species of this period, to the number of 133, begin to resemble those which enrich our landscapes. Already tropical plants are a.s.sociated with the vegetables of temperate climates; but they are not yet the same as existing species. Oaks grow side by side with Palms, the Birch with Bamboos, Elms with Laurels, the Maples are united to the Combretaceae, to the Leguminales, and to the tropical Rubiaceae. The forms of the species, belonging to temperate climates, are rather American than European.

The luxuriance and diversity of the Miocene flora has been employed by a German savant in identifying and cla.s.sifying the Middle Tertiary or Miocene strata of Switzerland. We are indebted to Professor Heer, of Zurich, for the restoration of more than 900 species of plants, which he cla.s.sified and ill.u.s.trated in his "Flora Tertiaria Helvetiae." In order to appreciate the value of the learned Professor's undertaking, it is only necessary to remark that, where Cuvier had to study the position and character of a bone, the botanist had to study the outline, nervation, and microscopic structure of a leaf. Like the great French naturalist, he had to construct a new science at the very outset of his great work.

[Ill.u.s.tration: Fig. 158.--Andrias Scheuchzeri.]

The Miocene formations of Switzerland are called _Mola.s.se_ (from the French _mol_, soft), a term which is applied to a _soft_, incoherent, greenish sandstone, occupying the country between the Alps and the Jura, and they may be divided into lower, middle, and upper Miocene; the middle one is marine, the other two being fresh-water formations. The upper fresh-water Mola.s.se is best seen at ningen, in the Rhine valley, where, according to Sir Roderick Murchison, it ranges ten miles east and west from Berlingen, on the right bank, to Waugen and to ningen, near Stein, on the left bank. In this formation Professor Heer enumerates twenty-one beds. No. 1, a bluish-grey marl seven feet thick, without organic remains, resting on No. 2, limestone, with fossil plants, including leaves of poplar, cinnamon, and pond-weed (_Potamogeton_). No.

3, bituminous rock, with _Mastodon angustidens_. No. 5, two or three inches thick, containing fossil Fishes. No. 9, the stone in which the skeleton of the great Salamander _Andrias Scheuchzeri_ (Fig. 158) was found. Below this, other strata with Fishes, Tortoises, the great Salamander, as before, with fresh-water Mussels, and plants. In No. 16, Sir R. Murchison obtained the fossil fox of ningen, _Galacynus ningensis_ (Owen). In these beds Professor Heer had, as early as 1859, determined 475 species of fossil plants, and 900 insects.

The plants of the Swiss Miocene period have been obtained from a country not one-fifth the size of Switzerland, yet such an abundance of species, which Heer reckons at 3,000, does not exist in any area of equal extent in Europe. It exceeds in variety, he considers, after making every allowance for all not having existed at the same time, and from other considerations, the Southern American forests, and rivals such tropical countries as Jamaica and Brazil. European plants occupy a secondary place, while the evergreen Oaks, Maples, Poplars, and Plane-trees, Robinias, and Taxodiums of America and the smaller Atlantic islands, occupy such an important place in the fossil flora that Unger was induced to suggest the hypothesis, that, in the Miocene period the present basin of the Atlantic was dry land--and this hypothesis has been ably advocated by Heer.

The terrestrial animals which lived in the Miocene period were Mammals, Birds, and Reptiles. Many new Mammals had appeared since the preceding period; among others, Apes, Cheiropteras (Bats), Carnivora, Marsupials, Rodents, Dogs. Among the first we find _Pithecus antiquus_ and _Mesopithecus_; the Bats, Dogs, and Coati inhabited Brazil and Guiana; the Rats North America; the Genettes, the Marmots, the Squirrels, and Opossums having some affinity to the Opossums of America. Thrushes, Sparrows, Storks, Flamingoes, and Crows, represent the cla.s.s Birds.

Among the Reptiles appear several Snakes, Frogs, and Salamanders. The lakes and rivers were inhabited by Perches and Shad. But it is among the Mammals that we must seek for the most interesting species of animals of this period. They are both numerous and remarkable for their dimensions and peculiarities of form; but the species which appeared in the Miocene period, as in those which preceded it, are now only known by their fossil remains and bones.

The _Dinotherium_ (Fig. 159), one of the most remarkable of these animals, is the largest terrestrial Mammal which has ever lived. For a long time we possessed only very imperfect portions of the skeleton of this animal, upon the evidence of which Cuvier was induced erroneously to place it among the Tapirs. The discovery of a lower jaw, nearly perfect, armed with defensive tusks descending from its lower jaw, demonstrated that this. .h.i.therto mysterious animal was the type of an altogether new and singular genus. Nevertheless, as it was known that there were some animals of the ancient world in which both jaws were armed, it was thought for some time that such was the case with the Dinotherium. But in 1836, a head, nearly entire, was found in the already celebrated beds at Eppelsheim, in the Grand Duchy of Hesse Darmstadt. In 1837 this fine fragment was carried to Paris, and exposed to public view. It was nearly a yard and a half long, and above a yard wide. The defences, it was found, were enormous, and were carried at the anterior extremity of the lower maxillary bone, and much curved inwards, as in the Morse. The molar teeth were in many respects a.n.a.logous to those of the Tapir, and the great suborbital apertures, joined to the form of the nasal bone, rendered the existence of a proboscis or trunk very probable. But the most remarkable bone belonging to the Dinotherium which has yet been found is an omoplate or scapula, which by its form reminds us of that of the Mole.

[Ill.u.s.tration: Fig. 159.--Dinotherium.]

This colossus of the ancient world, respecting which there has been so much argument, somewhat approaches the Mastodon; it seems to announce the appearance of the Elephant; but its dimensions were infinitely greater than those of existing Elephants, and superior even to those of the Mastodon and of the Mammoth, both fossil Elephants, the remains of which we shall have to describe presently.

[Ill.u.s.tration: Fig. 160.--Teeth of Mastodon.]

From its kind of life, and its frugal regimen, this Pachyderm scarcely merited the formidable name of Dinotherium which has been bestowed on it by naturalists (from de????, _terrible_, ??????, _animal_). Its size was, no doubt, frightful enough, but its habits seem to have been peaceful. It is supposed to have inhabited fresh-water lakes, or the mouths of great rivers and the marshes bordering their banks by preference. Herbivorous, like the Elephant, it employed its proboscis probably in seizing the plants which hung suspended over the waters, or floated on their surface. We know that the elephants are very partial to the roots of herbaceous plants which grow in flooded plains. The Dinotherium appears to have been organised to satisfy the same tastes.

With the powerful natural mattock which Nature had supplied him for penetrating the soil, he would be able to tear from the bed of the river, or lake, feculent roots like those of the Nymphaea, or even much harder ones, for which the mode of articulation of the jaws, and the powerful muscles intended to move them, as well as the large surface of the teeth, so well calculated for grinding, were evidently intended (Fig. 160).

The _Mastodon_ was, to all appearance, very nearly of the size and form of our Elephant--his body, however, being somewhat longer, while his limbs, on the contrary, were a little thicker. He had tusks, and very probably a trunk, and is chiefly distinguished from the existing Elephant by the form of his molar teeth, which form the most distinctive character in his organisation. These teeth are nearly rectangular, and present on the surface of their crown great conical tuberosities, with rounded points disposed in pairs to the number of four or five, according to the species. Their form is very distinct, and may be easily recognised. They do not bear any resemblance to those of the carnivora, but are like those of herbivorous animals, and particularly those of the Hippopotamus. The molar teeth are at first sharp and pointed, but when the conical points are ground down by mastication, they a.s.sume the appearance presented in Fig. 161. When, from continued grinding, the conical teat-like points are more deeply worn, they begin to a.s.sume the appearance shown in Fig. 160. In Fig. 162 we represent the head and lower jaw of the Miocene Mastodon; from which it will appear that the animal had two projecting tusks in the lower jaw, corresponding with two of much larger dimensions which projected from the upper jaw.

[Ill.u.s.tration: Fig. 161.--Molar teeth of Mastodon, worn.]

It was only towards the middle of the last century that the Mastodon first attracted attention in Europe. About the year 1705, it is true, some bones of this animal had been found at Albany, now the capital of New York, but the discovery attracted little attention. In 1739, a French officer, M. de Longueil, traversed the virgin forests bordering the great river Ohio, in order to reach the great river Mississippi, and the savages who escorted him accidentally discovered on the borders of a marsh various bones, some of which seemed to be those of unknown animals. In this turfy marsh, which the natives designated the Great Salt Lake, in consequence of the many streams charged with salt which lose themselves in it, herds of wild ruminants still seek its banks, attracted by the salt--for which they have a great fondness--such being the reason probably which had caused the acc.u.mulation, at this point, of the remains of so large a number of quadrupeds belonging to these remote ages in the history of the globe. M. de Longueil carried some of these bones with him, and, on his return to France, he presented them to Daubenton and Buffon; they consisted of a femur, one extremity of a tusk, and three molar teeth. Daubenton, after mature examination, declared the teeth to be those of a Hippopotamus; the tusk and the gigantic femur, according to his report, belonged to an Elephant; so that they were not even considered to be parts of one and the same animal. Buffon did not share this opinion, and he was not long in converting Daubenton, as well as other French naturalists, to his views.

Buffon declared that the bones belonged to an Elephant, whose race had lived only in the primitive ages of the globe. It was then, only, that the fundamental notion of extinct species of animals, exclusively peculiar to ancient ages of the world, began to be entertained for the first time by naturalists--a notion which laid dormant during nearly a century, before it bore the admirable fruits which have since so enriched the natural sciences and philosophy.

[Ill.u.s.tration: Fig. 162.--Head of the Mastodon of the Miocene period.

A, B, the whole head; C, lower jaw.]

Buffon gave the fossil the name of the _Animal or Elephant of the Ohio_, but he deceived himself as to its size, believing it to be from six to eight times the size of our existing Elephant; an estimate which he was led to make by an erroneous notion with regard to the number of the Elephant's teeth. The _Animal of the Ohio_ had only four molars, while Buffon imagined that it might have as many as sixteen, confounding the germs, or supplementary teeth, which exist in the young animal, with the permanent teeth of the adult individual. In reality, however, the Mastodon was not much larger than the existing species of African Elephant.

The discovery of this animal had produced a great impression in Europe.

Becoming masters of Canada by the peace of 1763, the English sought eagerly for more of these precious remains. The geographer Croghan traversed anew the region of the Great Salt Lake, pointed out by De Longueil, and found there some bones of the same nature. In 1767 he forwarded many cases to London, addressing them to divers naturalists.

Collinson, among others, the friend and correspondent of Franklin, who had his share in this consignment, took the opportunity of sending a molar tooth to Buffon.

[Ill.u.s.tration: Fig. 163.--Skeleton of Mastodon giganteus.]

It was not, however, till 1801 that the remains of the perfect skeleton were discovered. An American naturalist, named Peale, was fortunate enough to get together two nearly complete skeletons of this important animal. Having been apprised that many large bones had been found in the marly clay on the banks of the Hudson, near Newburg, in the State of New York, Mr. Peale proceeded to that locality. In the spring of 1801 a considerable part of one skeleton was found by the farmer who had dug it out of the ground, but, unfortunately, it was much mutilated by his awkwardness, and by the precipitancy of the workmen. Having purchased these fragments, Mr. Peale sent them on to Philadelphia.

[Ill.u.s.tration: Fig. 164.--Mastodon restored.]

In a marsh, situated five leagues west of the Hudson, the same gentleman discovered, six months after, a second skeleton of the Mastodon, consisting of a perfect jaw and a great number of bones. With the bones thus collected, the naturalist managed to construct two nearly complete skeletons. One of these still remains in the Museum of Philadelphia; the other was sent to London, where it was exhibited publicly.

[Ill.u.s.tration: Fig. 165.--Molar tooth of Mastodon.]

Discoveries nearly a.n.a.logous to these followed, the most curious of which was made in this manner by Mr. Barton, a Professor of the University of Pennsylvania. At a depth of six feet in the ground, and under a great bank of chalk, bones of the Mastodon were found sufficient to form a skeleton. One of the teeth found weighed about seventeen pounds (Fig. 165); but the circ.u.mstance which made this discovery the more remarkable was, that in the middle of the bones, and enveloped in a kind of sac which was probably the stomach of the animal, a ma.s.s of vegetable matter was discovered, partly bruised, and composed of small leaves and branches, among which a species of rush has been recognised which is yet common in Virginia. We cannot doubt that these were the undigested remains of the food, which the animal had browsed on just before its death.

The aboriginal natives of North America called the Mastodon the _father of the ox_. A French officer named Fabri wrote thus to Buffon in 1748.

The natives of Canada and Louisiana, where these remains are abundant, speak of the Mastodon as a fantastic creature which mingles in all their traditions and in their ancient national songs. Here is one of these songs, which Fabri heard in Canada: "When the great _Manitou_ descended to the earth, in order to satisfy himself that the creatures he had created were happy, he interrogated all the animals. The bison replied that he would be quite contented with his fate in the gra.s.sy meadows, where the gra.s.s reached his belly, if he were not also compelled to keep his eyes constantly turned towards the mountains to catch the first sight of the _father of oxen_, as he descended, with fury, to devour him and his companions."

The Cheyenne Indians have a tradition that these great animals lived in former times, conjointly with a race of men whose size was proportionate to their own, but that the _Great Being_ destroyed both by repeated strokes of his terrible thunderbolts.

The native Indians of Virginia had another legend. As these gigantic Elephants destroyed all other animals specially created to supply the wants of the Indians, G.o.d, the thunderer, destroyed them; a single one only succeeded in escaping. It was "the great male, which presented its head to the thunderbolts and shook them off as they fell; but being at length wounded in the side, he took to flight towards the great lakes, where he remains hidden to this day." All these simple fictions prove, at least, that the Mastodon has lived upon the earth at some not very distant period. We shall see, in fact, that it was contemporaneous with the Mammoth, which, it is now supposed, may have been co-existent with the earlier races of mankind, or only preceded a little the appearance of man.

Buffon, as we have said, gave to this great fossil animal the name of the Elephant of the Ohio; it has also been called the Mammoth of the Ohio. In England it was received with astonishment. Dr. Hunter showed clearly enough, from the thigh-bone and the teeth, that it was no Elephant; but having heard of the existence of the Siberian Mammoth, he at once came to the conclusion that they were bones of that animal. He then declared the teeth to be carnivorous, and the idea of a _carnivorous elephant_ became one of the wonders of the day. Cuvier at once dissipated the clouds of doubt which surrounded the subject, pointing out the osteological differences between the several species, and giving to the American animal the appropriate name of Mastodon (from ast??, _a teat_, and ?d???, _a tooth_), or teat-like-toothed animal.