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in Siberia. It has been frequently confounded with the mammoth or fossil elephant, and in North America it is named mammoth. In plate II. we have given an engraving of one of the grinding teeth of this animal. 2. Mastodon with narrow grinders.-The fossil remains of this species have been dug up at Simorre and many other places in Europe, and also in America. 3. Little mastodon with small grinders.This species is much less than the preceding, and was found in Saxony and Montabusard. 4. Mastodon of the cordilleras.-This species was discovered in South America by Humboldt. Its grinders are square, and it appears to have equalled in size the great mastodon. 5. Humboldien mastodon.-This, which is the smallest species of the genus, was found in America by Humboldt.

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Magnitudo et habitus elegans Gazellæ. 4. A. Minus. Dinito accessorio utrinque, in palmis et plantis, intermedios fere æquante.

All the fossil species of quadrupeds we have just enumerated have been found in the alluvial soil which covers the bottoms of valleys, or is spread over the surface of plains. All of them are strangers to the climate where these bones 5. A. Minimum. Statura caviæ cobayæ, e max

now rest.

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4. P. Curtum. Pedibus ecurtatis patulis. 5. P. Minus. Statura Ovis; pedibus strictis, digitis lateralibus minoribus.

Besides these five species found in the gyp sum quarries around Paris, remains of others have been discovered in other parts of France, either imbedded in the fresh-water limestone, or in alluvial soil. Cuvier enumerates and describes the following species:

6. P. Giganteum. Statura rhinocerotis. 7. P. Tapiroides. Statura bovis; molarium inferiorum colliculis fore rectis, transversis. 8. P. Buxovillanum. Statura suis; molaribus inferioribus extus sub gibbosis.

9. P. Aurelianensi. Statura suis; molarium inferiorum angulo intermedio bicorni. 10. P. Occitanum. Statura ovis; molarium inferiorum angulo intermedio bicorni. Anoplotherium, i. e. beast without weapons, referring to its distinguishing character, the want of canine teeth. This also is another fossil genus first discovered by Cuvier. The following are its characters :

Dentes 44, seria continua.

Magnitudo et habitus leporis.

illa tantum cognitum.

Habitatio omnium, olim in regione ubi nunc Lutetia Parisiorum.

Order VI.-PALMATA.
Family. Glires.

Castor, beaver. Two species are found in alluvial soil of different kinds :-the one, which is the castor fiber, or common beaver, has been found in marl pits and peat bog, in Perthshire and Berwickshire, in Scotland, and also in France; the other (on the shores of the sea of Azof by M. Fischer) differs from the former, and is named castor trogontherium.

Family. Fera.

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Laniarii primoribus similes, ceteris non lon- curred in the limestone of Solenhoff and Pappen

Primores utrinque 6.

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CLASS III. AMPHIBIA.

Order.-REPTILIA.

Testudo, tortoise.-Remains of this genus are met with in different parts of Europe; and tortoises, of unknown species, are found imbedded in coarse marine limestone in the environs of Brussels also in the coarse chalk or limestone of the hill of Saint Peter, near Maestricht. They are irregularly distributed throughout the masses of the rock, along with different marine productions, and bones of the gigantic monitor. All of them are remains of sea-tortoises, named chelonii by French zoologists; but of different species from those at present known. An unknown species of tortoise has been found in the limestone slate of Glaris; and remains of unknown species have been dug out of the rocks of the vicinity of Aix. Fossil fresh-water species have also been found in the gypsum quarries near Paris.

Crocodilus, crocodile.-Two extinct species of fossil crocodiles, nearly allied to the gavial (Lat. gangeticus), or gangetic crocodile, occur in a pyritical bluish-gray compact limestone, at the bottom of the cliffs of Honfleur and Havre : one of these species at least is found in other parts of France. It would also appear that the skeleton of a crocodile, discovered at the bottom of a cliff of pyritical slate, about half a mile from Whitby, by captain William Chapman, belongs to one of these species. Fragments of heads of crocodiles found in the Vicentine may be referred to the same species. The remains of an unknown species of fossil crocodile was found near Newark, in Nottinghamshire, by Dr. Stukely. The supposed crocodiles found along with fish in the copper slate, or bituminous marl slate, of Thuringia, are reptiles of the genus monitor. All these fossil remains of oviparous quadrupeds elong to old fleetz strata, far older than the flætz rocks that contain unknown genera of true quadrupeds, such as the palæotheriums and anoplotheitums; which opinion, however, does not oppose the finding of the remains of crocodiles with those of these genera, as has been done in the gypsum quarries.

Monitor.-In the quarries of Maestricht there occur remains of a large fossil monitor. This, which is one of the most celebrated of all the fossil species of oviparous quadrupeds, occurs in a soft limestone which contains flint, and the same kinds of petrifications as are observed in the chalk near Paris. It had engaged the attention of enquirers in 1766, and up to the present day has not ceased to be an object of discussion and investigation. Some have described it as a crocodile, others as a whale; and it has even been arranged along with fishes. Cuvier, after a careful study of its osteology, ascertained that it must have formed an intermediate genus between those animals of the lizard tribe which have a long and forked tongue, and those which have a short tongue and the palate armed with teeth. The length of the skeleton appears to have been nearly twenty-four feet. The head is a sixth of the whole length of the animal; a proportion approaching very near to that of the crocodile, but differing much from that of the monitor, the

head of which animal forms hardly a twelfth part of the whole length. The tail must have been very strong, and its width at its extremity must have rendered it a most powerful oar, and have enabled the animal to have opposed the most agitated waters. From this circumstance, and from the other remains which accompany those of this animal, Cuvier is of opinion that it must have been an inhabitant of the ocean.

Salamandra, salamander.-In the valley of Altmühl, near Aichsted and Pappenheim, and at Aeningen, there is a formation of calcareous slate, belonging to the Paris formation, rich in petrifactions. One of the most remarkable of these is that described by Scheuchzer, under the name homme fossile, and which some naturalists, as Gesner, maintained to be the siluris glanis of Linnæus, but which is, in reality, nothing more than an unknown and probably extinct species of salamander or proteus. It was found imbedded in the limestone of Aeningen.

Bufu, toad.-Remains of an animal of this tribe occur in the slaty limestone of Aeningen. Dr. Karg, who has published a long description of the Aeningen quarries, is of opinion, that this petrifaction is that of a common toad; whereas Cuvier is inclined to refer it to some species nearly allied to the bufo calamita.

Fossil saurus of Cuvier.-Only one specimen of this remarkable fossil animal has hitherto been found, and is now in the cabinet of the king of Bavaria. In regard to this specimen, it may be remarked, that some naturalists have taken it for a bird, others for a bat, but Cuvier is of opinion that it belongs to the class amphibia. Its true nature is still unascertained, although it appears more nearly allied to the class mammalia than to any of the others in the system.

CLASS IV.-PISCES.

The accuracy of La Cepede's list of the fossil fishes of Bolca, Aeningen, and Hessia, bas been much questioned by naturalists,' says Mr. Jameson, and Cuvier has hitherto paid but little attention to this branch of geology. He only enumerates in a very general way the few met with in the gypsum quarries around Paris. Five species are mentioned. The first described belongs to a new genus allied to that named amia, and is conjectured to be a fresh-water species. The second is nearly allied to two fresh-water genera, viz. the mormyrus of La Cepede, natives of the river Nile, and the pæcilia of Bloch, natives of the fresh waters of Carolina. The third appears to be a species of sparus, different from any of the present species. The fourth and fifth are very dubious. The bituminous marl slate of Germany abounds in fossil fishes. Schlottheim mentions a fossil fish found in this rock, as being five feet in length, and six inches broad, which he conjectures to belong to the genera cyprinus or Salmo. Petrified specimens, supposed of the salmo arcticus, are found in a bluish-gray clay in West Greenland. Single bones, as vertebræ, teeth, also scales of fishes, are found in the shell limestone, chalk, and in the rocks of the Paris formation.

Thus far we have travelled with the able translation of Cuvier's Essay edited by Mr. Jameson, and have only to regret that he did not complete the catalogue of existing remains in that work! Two or three important classes must be gleaned from other sources.

CLASS V.-AVES.

The remains of birds are rarely found in a fossil state. Bones, which may be considered as referrible to this class, are, however, imbedded in the calcareous schist of Oeningen, and in the oolitic schist of Stonesfield. The foot of a bird has been found incrusted in gypsum, near Montmartre; Blumenbach describes the bones of a water-fowl in the Pappenheim stone; and Faujas St. Fond has figured two feathers found in the calcareous stone of Vestena Nuova.

Cuvier, however, has not only ascertained the existence of fossil remains of this class, but has furnished the student with information to aid him in his investigations with respect to these fossils. The foot, he observes, in birds, has a single bone in the place of the tarsal and metatarsal bones. Birds, too, form the only class in which the toes all differ as to the number of joints, and in which this number, and the order of the toes which have them, is nevertheless fixed. The great toe has two; the first toe, reckoning on the inside, three; the middle, five; and the outermost five. The crocodile has the same number of phalanges; but, as these have a tarsal and metatarsal bone, they cannot be mistaken. Some birds have no great toes, but, in these, the other toes preserve the usual order: the ostriches and cassowars have three toes. Although the crocodile has the same number of phalanges, yet, as every one of the toes is supported by a particular metatarsal bone, the distinction is easily made. From an attention to the specific characters, Cuvier ascertained the existence of the remains of five or six different species of birds in the plaster quarries near Paris. Among these are the bones of a pelican, less than pelicanus onocratulus, and larger than P. carbo; of one of the larger curlews, with a naked neck (Tantalus, Gmelin); of a woodcock, a starling, and a sealark (Alouette de Mer). He also describes and figures a bird, found in the quarries of Montmartre, which appears to have fallen on its belly on the newly-formed gypsum, without having been quite involved in it; and having, probably whilst in this state, been deprived of its head and the whole of the right leg. The result of a careful examination of this fossil is, that it belongs to some exotic quail, rather larger than the one known in France. And here perhaps we may best introduce the ornithocephalus, although naturalists are not agreed as to its correct place. It is entirely a fossil genus. Cuvier refers it to the amphibia; others, as Blumenbach, to birds; Collini describes it as a fish; while Sömmering arranges it, as a bat, with the mammalia. The skull is enormous in proportion to the skeleton, the jaws themselves being longer than the body, and furnished with sharp incurvated teeth. The head of the O. longirostris resembles that of the curlew tribe, while the brevirostris more nearly resembles the bat, particularly the vespertilio

murinus. The orbits of the eyes are disproportionably large, and hence it is thought probable that, like the bat, it was a nocturnal animal, while, from the size of its jaws, it is likely that it fed on small flying insects. There are four legs (the hinder ones being of considerable length), and a distinct tail. There are no tarsal bones, only metatarsal bones and claws. Two species are described by Sömmering, the largest about a foot long, named O. longirostris; the other, which is less, O. brevirostris. See plate II. figs. 1 & 2.

CLASS VI.-INSECTA.

Insects also are of rare occurrence as fossils. Scheweigga mentions a perfect scorpion, different from the common genus, found in a piece of amber; ants of the present species have also been found in amber: supposed larvæ of the libellula and ephemera genera have likewise been mentioned, and the elytra of coleopterous insects as occurring in the Stonesfield slate.

CLASS VII.-RELIQUA OCEANA. We are compelled to rank under this general head all the crustacea, mollusca, radiarii, and polypi of authors. Of the first the mutilations are so great, and they are so enclosed, that often nothing is to be seen but parts of the thorax or upper surface of the body: the antennæ and feet are commonly broken and separated from the body; while the under surface, or numerous pieces of the plastron, or sternum, giving attachment to feet composed of many articulations, present also the external parts of the mouth. The want of the antennæ and feet induced Desmarest to restrict the distinctions to characters obtained from the shell or thorax. The various prominences of the latter, he continues, are not irregular and accidental; on the contrary, in all the genera the disposition of these inequalities is constant, and subjected to certain laws. We have been the more inclined, he remarks, to admit these relations, that it is known at a certain period of the year all the crustacea, after. having lost their old solid envelope, are covered with a delicate skin, which hardens in its turn, and at the end of a few days changes into a crust equally resisting with that which it substitutes; and we might presume that in the first moments the new skin moulded itself to a certain point upon the internal organs, and that its ossification was subsequently influenced by the motions peculiar to these organs, or by the greater or less development of each of them. He describes on this plan twenty genera, and a considerable number of species from different parts of Europe, Asia, and Africa. Many occur in Great Britain, principally in England, in the chalk formations, as well as in the plastic clay of Sheppey and other places.

Mollusca.-Fossil shells are perhaps the most abundant of all organic remains: and occur from the size of several feet in diameter to microscopic objects. They are divided into univalve, bivalve, and multivalve shells.

Univalve shells with but one chamber are called unilocular, and of these between seventy and eighty genera have been specified; while of the multilocular, or many chambered univalves, not more

than twenty-five occur. Dr. Montfort, author of an important work, Conchyliologie Systematique, has, indeed, with much discrimination separated the multilocular univalves into many more genera: the microscopic shells into sixty; and those which are within the power of the naked eye, being those which had been included in nautilus, ammonites, belemnites, orthoceratites, spirula, scaphites, nummulites, and siderolites, into forty genera; forming almost every shell, marked by a slight difference, into a distinct genus. These separations, although perhaps founded on accurate discrimination, appear, as Mr. Parkinson observes, to be too frequent; their multiplicity bears too much on the memory, and deprives it of the aid which it seeks to derive from classification. A more intimate knowledge of their nature and characteristics seems to be necessary before an appropriate arrangement of them can be adopted. The larger tribe has been separated into twenty-two genera, all of which have been found in a fossil state: whilst one genus only, nautilus, is known to exist in a recent state. Two opinions are entertained respecting this great disproportion between the number of fossil and of recent shells of this tribe. Some suppose that those genera, of which only fossil shells are found, have become extinct; whilst others bel eve that these shells are still existing in a recent state: but are pelagian shells, their inhabitants constantly residing at the bottom of the deep. This opinion is entertained by some of the latest French writers.

An examination of these shells proves, how ever, according to Mr. Parkinson, that, so far from their inhabitants having been destined to a constant residence at the bottom of the ocean, they possessed, beyond all other testaceous animals, the power of rising up to, and remaining at, the surface of the sea. Supposing them still to live, they would occasionally, as the nautilus is, be seen at the surface; but, not a single instance being known of a shell of these genera having been thus seen, their existence may be reasonably doubted. The apparatus enabling the animal to raise or sink himself at pleasure is plainly discoverable in the fossil shell of the nautilus but the most important part of this organ, the continuous siphuncle, is not discoverable in the dried specimens of the recent shell. The shell is formed of a number, more or less, of chambers, divided by pierced septa. The animal resides in the largest and last formed chamber; an elastic tube, proceeding from the animal, passes through the pierced septa and the several chambers, and terminates in the first. Now, assuming that the office of this tube is analogous with that of the swimming bladder of fishes, it is by no means difficult to conceive how the requir ed changes of situation may be produced. The weight of the shell is so counterbalanced by the empty chambers, that the siphuncle passing through these chambers, accordingly as it is dilated with gaseous or with aqueous fluids, will alter the specific gravity of the whole mass, and cause it either to swim or to sink. Supposing

the animal to be lying at the bottom of the sea, saturated with food, and the siphuncle filled with a fluid; as the food is digested and decomposed, detached gas may pass into the siphuncle, and gradually take the place of the water; when, in proportion as the specific gravity of the whole mass is thus diminished, it will rise, probably into that region of the waters in which the food of the animal most abounds. Here, on obtaining sufficient food, or on alarm from an enemy, the animal admits water into the siphuncle, and immediately sinks. In all the other genera of this tribe, an apparatus, formed of vacant chambers and a membraneous siphuncle, exists, capable of producing similar effects with those produced by that of the nautilus; but necessarily differing in some respects, from variety of modification of the form and structure peculiar to each genus. The siphuncle is often very well displayed in sections of the orthoceratite, and in these this tube will be found to have been capable of being dilated to a very considerable extent.

With the nautilus agree in general at a ratio the orthoceratite, the. belemnite, and the baculite species: other abundant tribes of multilvers are the ammonites and nummulites; the former being the vulgar petrified serpents; and whole masses of limestone being entirely made up of the latter: as, for instance, that with which the pyramids of Egypt are built.

Bivalve fossils are so varied in their forms that we can only refer the reader for a description of them to Mr. Parkinson's Introduction, or some other of the various treatises on fossil conchology. The multivalves are of unfrequent oc

currence.

The

Radiaria. Of the echinus, or sea urchin family, a great variety is met with in several of the newer rocks. Some of the species resemble those at present met with in our seas asterias or sea star family, from their delicacy and frail structure, are rarely met with. The crinoidea, or encrinite family, abound in many strata, and in vast abundance, but very rarely in a living state. Blumenbach first conjectured their affinity to the radiaria; and Miller, in his late work on the crinoidea, has removed every doubt as to their true place in the system. The entrochites and encrinites belong to this family.

Polypi.-We may include under this head the different kinds of simple animals named polypi, and their coverings, termed polyparia The corals are polyparia, and many of these occur in a fossil state. The alcyonia and sponges are likewise to be included. In the fresh state the former are nearly as soft as sponge, but have openings on the surface, through which polypi project. They occur frequently in flints. Sponges are composed of horny fibres connected together by means of an animal jelly, but no distinct polypi have been detected in them. They occur in a fossil state, and are abundant in the flint and chalk formations. We add from Mr. Parkinson's work

A TABLE OF BRITISH FOSSIL SHELLS.

Each Genus and each Species being placed in the order of the Strata in which they occu

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