The range of the genus Ichthyosaurus seems to have begun with the Muschelkalk, and to have extended through the whole of the oolitic period into the cretaceous formation. In all these flattened bones the effects of pressure are confined to those parts of the skeleton, on which the armour would rest, and are such as occur in a remarkable degree in the Armadillo. Thus it appears, that the more perfect forms of animals become gradually more abundant, as we advance from the older into the newer series of depositions: whilst the more simple orders, though often changed in genus and species, and sometimes losing whole families, which are replaced by new ones, have pervaded the entire range of fossiliferous formations. The first specimen discovered in a state approaching to perfection, was that in the collection of the Duke of Buckingham, figured in the Geol. Fold-outs if any not included.
Date 1837 Source Google Book: Author Permission Public domain Public domain false false This work is in the in its country of origin and other countries and areas where the is the author's life plus 70 years or less. The discovery of animals of this kind, both in the secondary and tertiary formations, shows that the Marsupial Order, so far from being of more recent introduction than other orders of mammalia, is in reality the first and most ancient condition, under which animals of this class appeared upon our planet: as far as we know, it was their only form during the secondary period; it was co-existent with many other orders in the early parts of the tertiary period; and its geographical distribution in the present creation, is limited to the regions we have above enumerated. All these are associated with the remains of other animals that are marine; and though they differ both from living Turtles and from one another, they still exhibit such general accordance in the principles of their construction, with the conditions by which existing Turtles are fitted for their marine abode, that Cuvier was at once enabled to pronounce these fossil species to have been indubitably inhabitants of the sea. As this inferior condition of living Marsupialia shows this order to hold an intermediate place between viviparous and oviparous animals, forming, as it were, a link between Mammalia and Reptiles; the analogies afforded by the occurrence of the more simple forms of other classes of animals in the earlier geological deposits, would lead us to expect also that the first forms of Mammalia would have been Marsupial. About this Item: Wentworth Press, United States, 2016. Home has further remarked a peculiarity of the spinal canal, which exists in no other animals; the annular part Pl.
He justly adds, that these disruptions of the crust must, from the disturbances communicated to the incumbent waters, have been necessarily attended with diluvial action on the largest scale. The earth was probably at that time too much covered with water, and those portions of land which had emerged above the surface, were too frequently agitated by earthquakes, inundations, and atmospheric irregularities, to be extensively occupied by any higher order of quadrupeds than reptiles. I also ventured to apply the name Diluvium to the superficial beds of gravel, clay, and sand, which appear to have been produced by this great irruption of water. Unusual deviations from ordinary structure appear monstrosities only, until considered with reference to their peculiar use, but are proved to be instruments of perfect contrivance, when we understand the nature of the service to which they are applied: thus; the beak of the Cross Bill Loxia curvirostra, Linn. . The most anomalous of all the characters of P. The second relates to Theories which have been entertained respecting the Origin of the World; and the derivation of existing systems of organic Life, by an eternal succession, from preceding individuals of the same species; or by gradual transmutation of one species into another.
Fifteen species of Lophiodon have been ascertained. The bodies of the vertebrae also more nearly resemble those of certain fossil Crocodiles, than of Ichthyosauri or Lizards; they agree further with the Crocodile, in having the annular part attached to the body by sutures; so that we have in the neck of the P. The pages will not fall out and will be around for a lot longer than normal paperbacks. Every comparative anatomist is familiar with the beautiful examples of mechanical contrivance and compensations, which adapt each existing species of herbivora and carnivora to its own peculiar place and state of life. This work was reproduced from the original artifact, and remains as true to the original work as possible. They cannot, therefore, be correctly described as entirely different systems of nature, but should rather be viewed as corresponding systems, composed of different details.
As tbe action of all these forces will be rendered most intelligible by examples of their effects, I at once refer my readers for a synoptic view of them, to the section which forms the first of my series of plates. This print on demand book is printed on high quality acid-free paper. Illustrations, Index, if any, are included in black and white. The intrusion both of dykes and irregular beds of unstratified crystalline matter, into rocks, of every age and every formation, all proceeding upwards from an unknown depth, and often accumulated into vast masses overlying the surface of stratified rocks, are phenomena coextensive with the globe. In the case of the Megatherium, the relative proportions are reversed; the head is comparatively small, the neck is long, and the anterior part of the body but slightly loaded in comparison with its abdominal and posterior regions. Beneath this sand they remain interred like the stumps of palm trees, and the buildings of ancient Egypt.
As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. When we see the body of an Ichthyosaurus, still containing the food it had eaten just before its death, and its ribs still surrounding the remains of fishes, that were swallowed ten thou sand, or more than ten times ten thousand years ago, all these vast intervals seem annihilated, time altogether disappears, and we are almost brought into as immediate contact with events of immeasurably distant periods, as with the affairs of yesterday. Pursuing the analogies of construction, that connect the existing inhabitants of the earth with those extinct genera and species which preceded the creation of our race, we find an unbroken chain of affinities pervading the entire series of organized beings, and connecting all past and present forms of animal existence by close and harmonious ties. Thus, he observes, we may recognise a double origin of the rocky masses, the one by refrigeration from igneous fusion, which, as we have seen, he considered principally to be assignable to the primary and fundamental rocks, the other by concretion from aqueous solution. As the form of vertebrae by which it is associated with the class of fishes, seems to have been introduced for the purpose of giving rapid motion in the water to a Lizard inhabiting the element of fishes; so the further adoption of a structure in the legs, resembling the paddles of a Whale, was superadded in order to convert these extremities into powerful fins. It exhibits also casts of the perforations along the internal parietes, whereby the vessels entered obliquely from the exterior of the bone, to communicate with the marrow.
Fold-outs, if any, are not part of the book. The science professor in a crusty, conservative and clerical university had become a star. The small bowels only are thus detached from the body, the stomach and other viscera remain within it. We know from the fragment of a femur, in the collection of Mr. The same map, on a larger scale, appears in the second series of the Transactions of the Linnean Society of Normandy. Thirdly, we have remains of the same animals in caverns and fissures of rocks, which formed parts of the dry land during the more recent portions of the same period.
Each page is checked manually before printing. Strata thus loaded with the exuviæ of innumerable generations of organic beings, afford strong proof of the lapse of long periods of time, wherein the animals from which they have been derived lived and multiplied and died, at the bottom of seas which once occupied the site of our present continents and islands. Acting with their advice, and with the concurrence of a nobleman immediately connected with the deceased, Mr. General Ernouf also explains the occurrence of the scattered bones, by reference to a tradition of a battle and massacre on this spot, of a tribe of Gallibis by the Caribs, about the year 1710. Certain clay beds of the Wealden formation below the chalk, are so abundantly charged with microscopic shells of the Cypris Faba, that the surfaces of many laminæ into which this clay is easily divided, are often entirely covered with them as with small seeds.