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of the Indian and American Ocean, the Buccinum Plicatum of Jamaica, the Turbo Imbricatus of the Atlantic, the Murex Ramosus of the Red Sea and Persian Gulph, and the Murex Sinensis of the coast of Africa.

"That there are innumerable instances of the existence of fossil organized bodies in such situations as incontestably prove that the surface of the earth has undergone the most extraordinary changes, every geologist admits; but M. Brocchi shows, that some geologists have been rather hasty in their conclusions with respect to many of those fossil shells which were said to belong to climates far distant from that where they are found. Be fore we can decide upon the foreign origin of any fossil shell, it is obviously necessary to be well acquainted with those existing in the surrounding seas, not only along the coasts, but in the less accessible depths; and as the difficulty of acquiring this information is necessarily great, there should be a proportionate degree of caution in coming to that decision.

The Zoology of the Adriatic has been very accurately investi gated by Donati, Ginamni, Bianchi, Olivi, and Renieri. The work of Olivi, M. Brocchi considers by far the most valuable, It was published in 1792, under the title of Zoologia Adriatica, but was left unfinished by the premature death of the author.The same subject has since that time been followed up with great care by Renieri, Professor of Natural History in the University of Padua.

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We learn from the work of Olivi, that many of the shells which were considered as belonging exclusively to the Asiatic and American seas, are found in the Adriatic; and Renieri has discovered twice as many species as were known to his predecessor. To be convinced with how little accuracy the habitats of many shells have been given, it is only necessary to compare the thirteenth edition of the Systême de la Nature, with the Prodromus of the work of Renieri. He has found fifty-five different species that were supposed to exist only in distant seas. Of these, twelve were said to belong to the Indian Ocean, seven to the Indian Ocean and Eastern coasts of Africa, eight to the Western coasts of Africa, six to the American shores of the Atlantic, three to the Islands of Nicobar, near the Bay of Bengal, two to the coasts of South America, one to the Caspian, five to the European Ocean, and eleven to the North Seas. Besides these, he has also found in the Adriatic, ten different species, the habitats of which were unknown to Linnæus. Similar results to these have been obtained by Poli in his examination of the sea near Naples.

The same correction must also be made in regard to the ha

bitats of Zoophytes, and particularly the genus Isis and the Madrepores. Not many living species of these are found in the Adriatic; but they abound" in the Mediterranean, as appears from the work of Maratti, published at Rome in 1776.–Of these found in a fossil state, many different species have been found in the Mediterranean and Adriatic, which were said to belong to the Indian Ocean, the Red Sea, the West Indies, &c.

• If equally accurate researches were made in the Ichthyology of our seas, I am very confident that many of those fishes would be found which are described as inhabitants of the Indian and American seas, and that we should discover the prototypes of

many

of those now existing in a fossil state at Monte Bolca. Of the one hundred and twenty-three species described by Volta, there are only thirtyseven belonging to the European seas, according to the classification of that author.'- "The more our researches are multiplied, the more we shall find that the number of species of shells belonging exclusively to particular latitudes, is less considerable than is generally supposed. If it cannot be maintained that difference of climate does not affect marine organized bodies, it is certain at least that its ef. fects are much less considerable upon them than upon the organic productions of the land, as the sea is not subject to the same changes of temperature as the atmosphere is. Although it may not be true, either, that in all places equally deep, the water is of the same temperature under every parallel, as some have asserted; it is, however, distinctly cold, even under the tropics, at very considerable depths ; So that if difference of climate does materially affect some shells, it can only be those which live in shallow water, or near the coasts. p. 157-159.

In the catalogue which Lamark has given of the fossil shells that have been found in the neighbourhood of Paris, there are about five hundred species; and it is wonderful how few of them resemble those found in the Sub-Apennine Hills, and how many . genera there are among thein, wholly unknown in Italy. But the most remarkable difference in the fossil shells of the two countries, is in those of which the prototypes are unknown. These greatly predominate in France, and, with a few exceptions, are wholly different from those that exist in Italy. In the latter country many species are wanting which are common in the neighbourhood of Paris; and many occur in Italy that have not been found there. There arc, moreover, many shells of constant occurrence in the marl, and which are now common in the Adriatic and Mediterranean Seas, that do not appear to have been met with by Lamark.

Besides these vast collections of fossil shells, the remains of many other tribes of marine animals are found in the SubApennine Hills. The most remarkable of these are the remains of great whales, not only in separate bones, but in

entire skeletons. They have been found in various parts of Tuscany, in the territory of Bologna, in Piedmont, and in the neighbourhood of Feltre, a country situated about 1200 feet above the level of the sea. Near Castell'Arquato in the territory of Placentia, a skeleton was found nearly entire, measuring 21 feet in length. All the bones were in their natural situation, and had undergone no other change than the loss of the animal gluten. Besides this skeleton, there were found a part of one still larger, and many detached vertebræ, ribs, and jawbones of the same animal. There were also found in the same neighbourhood, the skeleton of a dolphin six feet long, a part of another skeleton belonging to an animal of the same tribe, and the jawbone of a dolphin quite petrified, containing the greater part of the teeth, with their natural enamel preserved.

All these animal remains, and others of the same sort, which have been dug up in various parts of Italy, are found in the blue marl. Some of the bones found in the territory of Placentia, and the portion of the whale's jawbone found in Valdarno Inferiore, which is in the Museum of Florence, are encrusted with oyster-shells, which must have lived and grown upon them. . So that it is quite evident, as M. Brocchi remarks, that these skeletons must have remained, as such, for a considerable time at the bottom of the sea, and that they cannot be considered as the remains of animals carried by some sudden inundation to the places where they were dug up.

However striking the occurrence of those bones, in such situations, may be, it is still more extraordinary to find, in the same places, the remains of those great land animals that now inhabit the torrid zone.

“ Among all the phenomena of Geology, there is none more wonderful than this, or one more worthy of deep reflection ; nor is there any fact which is more puzzling to the ingenuity of Naturalists, who bewilder themselves in a labyrinth of conjecture, how the elephant, the rhinoceros, and the hippopotamus, should be found buried in our climates. The multitude of these skeletons renders the fact still more surprising. Targioni calculates the number of elephants' bones that had been dug up in Valdarno Superiore in his time, equal to those of twenty individuals; and this number has been so much augmented by subsequent discoveries, that the district may be considered as a vast cemetery of these gigantic animals. It was ascertained that, before the peasants of the neighbourhood thought of preserving these bones for the sake of selling them to the curious, some of them had been in the habit of surrounding their gardens with palisades of the tibia and thigh-bones of the elephant. One of the persons who are in the habit of searching for these bones, accompanied me to the hill of Poggio Rosso, where, after having VOL. XXVI. No. 51.

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removed the earth in four or five places, he found a large elephant's tusk from thence we went to the Colle degli Stecconi, and with the same facility he dug up a large grinder, with some of the bones of the cranium, and two tusks-one of which was nearly five feet long, and eight inches in its greatest diameter. In Valdarno Supe riore, they also find bones of the rhinoceros, the hippopotamus, stag's horns, jaw-bones and teeth of the mastodonton, and other herbivorous animals, which seem to belong to the horse and the ox. The district where these remains are found in greatest abundance, is that on the right bank of the Arno, between Figline, Castelfranco, and San Giovanni, and from Renaccio to Montanino; from whence were obtained the chief part of those that are in the Royal Museum of Florence, in that of professor Targioni, and those belonging to the Accademia Valdarnese di Figline, who are in possession of a very fine series, collected chiefly by the Padre Molinari, a monk of Vallombrosa.' p. 179.

These remains are not confined to Valdarno nor to Tuscany, but are found in different places on both sides of the Apennines, from Lombardy to Calabria. M. Brocchi gives a list of the most remarkable places where they have been found, distinguishing the different species of animals. He enumerates forty-six specimens of the bones of elephants, found in different situations -in Piedmont-near Verona-in the territories of Pavia, Tortona, Placentia and Bologna-in Puglia, Basilicata, and Calabria-in the neighbourhood of Pozzuoli near Naples-twelve different places near Rome-near Viterbo, Todi, Perugia and Cortona-in Valdarno Superiore and Inferiore, near Leghornand also at Palermo in Sicily, which last country appears to abound in fossil bones. On one occasion, there was found in the neighbourhood of Rome, the entire skeleton of an elephant; but it was unfortunately destroyed by the workmen. He describes fifteen specimens of the Mastodonton found in different parts of Piedmont and Lombardy, and on both sides of the Apennines, but not farther south than Perugia. At Castell' Arquato, there was found the greater part of the skeleton of a rhinoceros; and in Valdarno Superiore, and the territory of Perugia, different bones of the same animal. In Valdarno Superiore, in Piedmont, and in the neighbourhood of Verona, remains of the Hippopotamus have been dug up; and many specimens of the head and horns of the Urus have been found in the territories of Verona, Pavia, Siena, in the Marca di Ancona, and near Rome. A head of the Irish Elk was found in Oltrepò Pavese, another in the vicinity of Voghera, and a third near Lodi Vecchio on the banks of the Lambro.

The bones of all these animals are found, in general, a few feet below the surface; and the soil in which they are buried is commonly a yellow sand, generally calcareous, but sometimes almost whol

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ly siliceous. Of this last description is the soil in many parts of Valdarno Superiore, which does not effervesce with acids, and is composed of grains of quartz and scales of mica, mixed with a reddish yellow oxide of iron. When it is not agglutinated, it is called Sansino by the inhabitants ; and when, as often the case, it is consolidated, they call it Tufo. The elephant's tusk found by Canali near Perugia, was in a field covered with rounded pebbles; and that mentioned by Baccio as having been dug up near Rome in his time (1580), appears to have been discovered in the midst of a coarse gravel. These fossil remains of land animals are not confined to the sand and gravel alone, but are also sometimes found in the blue marl when it occupies the surface, and is not covered by other deposits. I have seen instances of this in Valdarno itself, on the Colle degli Stecconi, where a part of the head of an elephant was dug out of it in my presence. The tusk of Belvedere near Jesi was in a soil of the same sort, as well as the jawbone of the Rhinoceros found by Canali in the territory of Perugia. One of the vertebræ of the skeleton of the rhinoceros found at Castell'Arquato was in the marl, while all the other bones were in the siliceo-calcareous sand lying over it.' p. 195.

It is a very curious circumstance, and one of considerable importance in the physical history of the country round Rome, that bones of the elephant have been found there, imbedded at the depth of twenty feet, in the volcanic tufo.

Fortis, in his Memoires sur L'Hist. Nat., has said, that the tusk of an elephant was hewn out of a bed of stone of ancient formation, containing exotic marine remains, found near Lega horn. From this description one might suppose, that it was a solid limestone similar to that of the Apennines; but M. Broc. chi informs us, that this stone is a calcareous tufo of a cellular texture, having grains of sand of different sizes imbedded in it; and the shells it contains are so broken, that it is impossible to say to what species they belong. There is a considerable bed of it, which is partly washed by the waves of the sea; and it is gradually increasing in extent, by the agglutination of the grains of sand by a calcareous cement. This is evidently a rock which has been formed in the same manner as that on the shore of Guadaloupe, in which the human skeleton was found; but from M. Brocchi's account of the rock near Leghorn, that of Guadaloupe is of a much more consolidated texture.

We have already mentioned, that some of the whale's bones found in the territory of Placentia, and in Valdarno, were encrusted with oyster-shells; but it is still more remarkable, that some of the elephant's bones dug up in Valdarno, and in the territory of Placentia, have also been found covered with the same shells, and adhering to them so firmly, that they could not be detached without breaking the bone. All the

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