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Cuvier has ascertained and classified the fossil remains of 78 different quadrupeds in the viviparous and oviparous classes. Of these, 49 are distinct species, hitherto entirely unknown to naturalists. Eleven or twelve have such entire resemblances to known species, as to leave no doubt of their identity. The remaining 16 or 18 have considerable resemblance to known species; but the comparison has not been made with so much precision as to remove all doubt. Of the 49 new species, 27 are referable to seven new genera, while the other 22 are referable to genera or subgenera already known. The whole number of genera to which the fossil remains of quadrupeds hitherto investigated are referable, are 36, including those belonging both to known and unknown species.

Of these 78 species, 15 belong to the class of oviparous quadrupeds, while the remaining 63 belong to the mammiferous class. Of these, 32 species are hoofed animals not ruminant, twelve are ruminating animals, seven are gnawers, eight carnivorous quadrupeds, two toothless animals of the sloth genus, and two amphibious animals.

Professor Buckland of Oxford, one of the most zealous and successful cultivators of geology of modern times, has added a new view respecting the existence of animal remains in caverns, where they frequently occur in vast quantities, enclosed in stalagmite or hardened mud, which has preserved them from the action of the weather. Into the very ingenious details which he has given in his various publications on this subject, particularly in his Reliquiæ Diluvianæ, we have not left ourselves space to enter. These caverns, particularly the celebrated one of Kirkdale in Yorkshire, which he first described in the Philosophical Transactions, he conceives to have been the habitation of hyænas before the Flood. These animals were in the habit of dragging their mutilated prey into their habitations. Hence the numerous remains of bones found in these caverns, all gnawed, according to the custom of these animals. Their hardened excrements he also showed to exist in the caverns, and to be mixed with the gnawed bones. The bones found in the cave at Kirkdale were those of hyænas, bears, tigers, foxes, wolves, elephants, rhinoceroses, hippopotamuses, oxen, deer, &c. They were all, however, the bones of species no longer existing. The reason why no human remains are ever found in these caverns, naturally occurs. In case of a deluge, the human race would not betake themselves to caverns; they would naturally endeavour to escape by betaking themselves to the highest eminences of the country where they lived. If the diluvium followed them there, destruction would be unavoidable; because no further or

higher retreat would remain for them. Hence the reason, he thinks, why no human bones have been found in such caverns. But, within these two or three years, several caverns have been explored in the South of France, in which human bones have been found, along with those of lost species of animals, and likewise of animals at present existing in the earth. These bones are imbedded in stalagmite, or dried mud. The bones with which they are mixed have the usual gnawed appearance, and are mixed with the album græcum observed in the cavern at Kirkdale.

The first of these caverns occurs at Bize, in the department of Aude. The bones are found fixed to the rock by a stalagmitical calcareous cement. Fragments of rude pottery occur jumbled together with these bones. Human teeth occur, along with sea and land shells, similar to those still found in the neighbourhood. The teeth resemble the first molar, and preserve their enamel; but the roots are so much changed, as to adhere firmly to the tongue. These bones are found imbedded in a red mud, and likewise in a black mud, lying over this last. The shells are the cyclostoma elegans, the bulimus decollatus, Helix nemoralis, and nitida; associated with these land shells, are the Pecten Jacobæus, Mytilus edulis, and Natica millepunctata. Among the extinct bones are those of a species of cervus, and of the auroch, which still exists, but confined to some Lithuanian fo

rests.

The second cavern, Pondres, is distant a couple of leagues from the first. It was quite filled with dried mud, in which were lodged the bones and the album græcum met with in other caves. Human bones and fragments of pottery were mixed with bones of the rhinoceros, wild boar, a small species of horse, bos, cervus, sheep, stag, bear, badger, hyæna, &c., some of these belonging to extinct species, some to living species. The third cavern, Souvignargues, is not far from the other two, and contains human bones, similarly mixed with those of other animals.

If it were not for the fragments of pottery, we might suppose that the human bones have been occasioned by the hyenas accidentally dragging pieces of human bodies to their caverns, along with their other prey; and these human beings may have met with an accidental death, or have been destroyed by animals of prey. But the occurrence of pottery, and of the bones and shells of animals still existing, would rather lead to the notion, that these caverns may have been inhabited at a very remote period, but still after the period of the deluge, by some wild animals of the country; or that some solitary human beings may have taken refuge there, and that afterwards the

caverns may have been filled with mud by some subsequent and partial deluge of which, doubtless, many have occurred since the earth was inhabited by the human race.

The porphyry and trap rocks, which constitute so prominent a part of the surface in that part of Scotland which we inhabit, are situated in an inconformable position to the other, or irregularly interposed between them; though sometimes they seem to be associated with, and to alternate with, the primary or secondary rocks. They must have been formed at a different time from the primary and secondary strata on which they lie. They never contain any animal or vegetable remains, though such remains often occur in rocks with which they alternate, or which are situated very near them. They frequently cut through the other rocks in the form of thick walls or dykes; and when they thus pass through a coal-field, the coal in their immediate neighbourhood is usually deprived of its bitumen, and converted into coke, just as if it had been exposed to heat. These, and many other circumstances, which we have not room to enumerate, led Dr Hutton to conclude, that these rocks had been formed by heat, and that they had been forced up from below in a liquid form, and thus covered, or penetrated and deranged, the formations through which they passed. This opinion, after having been controverted with much zeal by the followers of Werner, has gradually made its way, and seems at present to be almost generally admitted by geologists.

The word porphyry signifies at present, a rock having a compact basis, through which are scattered crystals of some other mineral. The basis gives the name to the porphyry, and is either felspar, pitchstone, or claystone. In this country, it usually occupies the summits of the mountains. This may be very well seen in Ben-Nevis. The lower part of that mountain is granite, but the central cone is felspar porphyry. If we examine this mountain, we can scarcely doubt that the porphyry has been pushed up through the granite, and formed the summit. It seems to have made its way south, for the summits of the mountains of Glenco consist of the same kind of porphyry.

The curious dyke of pitchstone porphyry, called the Skure of Egg, in one of the Hebrides, constitutes another specimen of porphyry, that seems to have made its way to its present position in a fluid state. The same remark applies to the dykes of pitchstone porphyry at Brodik, in the Isle of Arran. They were doubtless connected with the great porphyry formation in the south of Arran, though that connexion can no longer be traced. The claystone porphyry constituting the summit of the Pentlands, so conspicuous from Edinburgh, and so common in the

Ochil Hills, exhibits no trace of having ever been in a state of fusion. But in the Ochils, at least, the claystone porphyry is› obviously connected with the felspar porphyry, and seems to pass into it; so that the relation of claystone to felspar is probably much closer than we at present suppose.

The word trap was first applied by Riman to a set of hills which occur in Sweden; and he gave them that name, he says, because the rocks of which they are composed broke in rectangular fragments like sandstone. Werner afterwards limited: the signification to certain rocks distinguished by the hornblend which they contain. The most important trap rocks are greenstone, amygdaloid, basalt, porphyry slate, wacke, and trap-tuff.

Greenstone is a mixture of felspar and hornblend, or sometimes of felspar and augite. It is very common about Edinburgh; Salisbury Crags, the Castle-hill, the rocks of Inchkeith, and many hills on the south coast of Fife, consisting partly of it. It bears very unequivocal marks of having been forced from below, upwards, in a state of fusion, and of having made its way through the other rocks with which it is associated.

Amygdaloid is a rock containing almond-shaped cavities, usually filled with calcareous spar, and various specimens of the numerous tribe of zeolites in a state of crystallization. Sir James Hall and Mr Gregory Watt threw much light upon the formation of this stone, and of greenstone, by their experiments. It seems to have been subjected to a strong heat while under great pressure. Basalt and porphyry slate have a great affinity to greenstone, and have undoubtedly been formed under similar circumstances.

We cannot afford space to enter into the details which would be necessary to show that all these rocks have been formed by the action of heat, and that they have all been either in a soft state, or in a state of fusion. But the subject has so long occupied the attention of geologists, and the numerous objections of Werner and his disciples have been so carefully examined and so fully refuted, that we are not aware of any difference of opinion at present existing on the subject. All admit that the porphyry and trap rocks have been formed by heat, and that they have been pushed up from below; but probably at a time when the whole was either covered by the ocean, or subjected to an enormous pressure by means of incumbent rocks, which have since been removed.

Thus, since the earth was inhabited both by vegetables and animals, since the primary and secondary rocks have been de-. posited, it has undergone a partial, but prodigious alteration, by the action of heat. Immense tracts of melted stony matter have

been forced up, and have made their way over a great extent of surface. These alterations and catastrophes must have taken place before the earth became inhabited by the human race; otherwise, had any rational creatures existed on it, and escaped the devastations which must have taken place, some traditionary information concerning such tremendous occurrences must have been handed down to us.

From the preceding sketch, imperfect and limited as it necessarily is, some idea may be formed of the numerous changes to which the earth has been subjected since its ori-, ginal creation, and the vast number of ages which must have elapsed before it became fit for the habitation of man. Well may it be predicated of the Deity, that with him a thousand years are as one day, and one day as a thousand years! May not a similar series of changes be going on in the other planets belonging to the solar system; and may it not be possible that they are not yet so far advanced as in our planet; and may not this be the reason why none of them as yet is possessed of an atmosphere similar to ours?

ART. IV.--Notes on the Bedouins and Wahabys: Collected during his Travels in the East, by the late JOHN LEWIS BURCKHARDT. Published by the authority of the Association for the Discovery of the Interior of Africa. 4to. London: 1830.

T HOUGH all the works of this enterprising and unfortunate traveller have greatly contributed to the increase of our knowledge, it is in the posthumous publications which bear his name that we find the largest mass of interesting and curious information.

The observations contained in his first works on the backsettlements of Syria and Palestine, and on the rude and brutal slave-merchants of the Nubian Desert, cannot rival in interest those of the posthumous volume in which he has so fully unveiled the mysteries of Mahommedan pilgrimage.* An equal rank may be assigned to the present, which throws new light on a race, who have long stood single among the nations, retaining from age to age a character in which lofty virtues and odious vices are strangely combined. The volume embraces also a different, but kindred subject, giving the most ample and authentic account that has yet appeared of the Wahaby power, which was

* See No. 99, p. 164.

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