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force continued unimpaired even subsequently to the formation of some tertiary deposits, those geologists who contend it is now in the wane must reason from a very limited number of facts indeed.

Both Mr. Poulett Scrope* and Dr. Daubenyt in their recent publications agree in considering that the effects produced at present by earthquakes and volcanos are at least analogous in kind, if inferior in degree, to those that have resulted from similar agents at remote æras. More than 170 volcanos are at present in activity on the land, even if separate orifices at a short distance from one another be reckoned as one volcano ; and there is reason to believe that there are at least as many, and probably a much greater number, beneath the sea—the power of which latter in throwing up islands and altering the bed of the sea is well known.

The chain of extinct volcanos described by the above mentioned authors in Auvergne, the latest of which became extinct before the period of any historical records; the streams of lava, which can be traced from their craters to the choked up vallies, and to the ancient courses of rivers thereby diverted into new channels; these and many more phenomena raise the strongest presumption in favour of the great antiquity of some parts of the European continent. I When we consider the deltas of large rivers, the strata at the bottom of freshwater lakes in Germany, Italy, and England, but, above all, the recent deposits at the bottom of the great American lakes Superior and Huron, inclosing shells of the very species now inhabiting those lakes and exposed to view in consequence of the subsidence of the water occasioned by the partial destruction of their barriers, we can affirm with certainty that modern freshwater deposits, of no inconsiderable thickness, far exceed in area the ancient freshwater formations, at present described. As to the scale on which submarine strata are now formed, we remain, of course, in comparative ignorance, but it is certainly more considerable than has been supposed by many. Whether the coral reefs of the East Indian archipelago are built up from an unfathomable depth, as Flinders imagined, or are based on submarine volcanos, as Kotzebue and more modern writers suppose, we are at least certain, from the manner in which these zoophytes increase, and from the necessary accumulation of their broken fragments, that those aggregations of calcareous matter cannot be of slight depth, while we know that their superficial extent is immense. Captain King, in his late survey of Australia, sailed along a continued

* Considerations on Volcanos, by G. Poulett Scrope, Esq. London. 1825.

+ See p. 2. Description of active and extinct Volcanos, by Charles Daubeny, M. D. London. 1826.

Letters to Professor Jam on the Volcanus of Auvergne, by Charles Daubeny, M. Đ. F. R.S. Dr. Bigsby in the Journal of Science, &c. No. 37. pp. 262, 263. KK 4

line + Scrope, on Volcanos, p. 9.

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line of coral reef for 700 miles, interrupted only by a few intervals

a not exceeding 30 miles. These reefs stretch from the north-east coast of Australia towards New Guinea, and very far exceed in length any chain of secondary mountains in Europe. It is unnecessary to remind the geologist, how close a resemblance masses of such zoophytes intermixed with calcareous sand and the exuviæ of testacea so abundant in tropical seas, must bear to the greater part of the ancient oolitic formations. A calcareous concreted sand-rock unquestionably of modern formation has been found to exist in Australia throughout a space of no less than 25 degrees of latitude, and an equal extent of longitude, on the southern, west, and north-west coasts. We might adduce many more examples from the Mediterranean, and other seas, but we shall content ourselves with stating, in conclusion, that the stone of Guadaloupe containing the human skeletons is, in parts, as compact as the greater proportion of our secondary rocks. This description of rock is very common in the West Indian Archipelago, and increases rapidly; it forms the gained land, which has extended the plain of Cayes in St. Domingo, and there the remains of pottery and other human implements have been found at the depth of 20 feet.*

There are still, it may be said, some conglomerate rocks in Europe and in America, such, for instance, as are remarkably exhibited both in the old and new red sandstone formations, that evince a continued and destructive action over

a great extent of the globe, unparalleled by existing causes. That the sudden elevation or subsidence of land might be attended with such ca, tastrophes will, however, hardly be denied. Earthquakes and volcanos are, for the most part, characterized by brief periods of intense activity, interrupted by irregular intervals of quiescence.t Of the duration of these intervals we must be, at present, altogether ignorant, for centuries of complete tranquillity have interyened between recorded eruptions of volcanog accompanied with violent shocks of earthquakes.-----But we cannot allow ourselves to speculate farther on these topics, and return to our zoological observations.

Of birds an extremely limited number have hitherto been dis. covered in a fossil state, and their scarcity forms a striking contrast to the abundance of other kinds of vertebrated animals. In the gypsum of Paris, however, before mentioned, several well defined species have been found and described by M. Cuvier. They were coeval with the Palæotherium and its contemporaries, and were different, like them, from any species now living; yet, with Cuv. Discours sur les Rev. &c. p. 134.



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respect to the general laws of co-existence and structure, and all that relates to the nature of their organs and their essential functions,' they were the same as those of our own time.'*

But in oviparous quadrupeds, remarkable alike for their magnitude and organization, nature has, in ancient epochs, teemed throughout these latitudes with a prolific power not exerted at present even between the tropics. These quadrupeds occur in strata of far more ancient date than the viviparous class. They make their first appearance in England in the lias, where many skeletons are procured in so perfect a state that the most exact knowledge has been obtained of their structure. In the volume before us are two excellent papers, by. Mr. Conybeare, on the osteological characters of the fossil genera Ichthyosaurus and Plesiosaurus, both first discovered and determined in this country. • The Ichthyosaurus is an animal entirely sui generis ; possessing, however, sufficient analogies with the Saurian order to justify our referring it to that great natural division :-it holds an intermediate place between tbe crocodile and lacertæ.' Like the Cetacea it was exclusively an inhabitant of the sea ; its eyes were of an enormous size, its neck short, its tail extremely long, its paddles broad and flat, and its whole frame admirably adapted for passing with rapidity through the water. Mr. Conybeare has ascertained four distinct species: one of these, I. communis, sometimes exceeds twenty feet in length; and I. platyodon was yet more gigantic.

The Plesiosaurus was still more extraordinary. Of this genus five species are ascertained. An almost entire skeleton of one of these--P. dolichodeirus, found in lias at Lyme Regis in Dorsetshire, and now in the possession of the Duke of Buckingham, is figured in this volume. This specimen does not exceed eight or nine feet in length, but the same species sometimes attained the length of twenty feet. It was distinguished from all known oviparous and viviparous quadrupeds, by a thin slender neck, equalling or exceeding the body in length, and composed of above thirty vertebræ.

. This great increase,' observes Mr. Conybeare,' of the number of joints in the neck is the more remarkable from the rigour with which nature appears in most cases to have enforced the law of a very limited number. In all quadrupedal animals, in all the mammalia, (excepting only the tridactyl sloths, which have nine,) the series is exactly seven ; and so strict is this rule, that even the short and stiff neck of the whale, and the long and flexible neck of the cameleopard are formed out of the same elementary number; the vertebræ in the former instance being extremely thin and anchylosed together, and in the latter greatly elongated. Rep

* Cuv. Oss. Foss. vol. iii. pp. 15. 255.

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tiles possess only from three to eight cervical vertebræ ; birds approaching in this more nearly to the present species, but still falling greatly short of it, bave from nine to twenty-three, the number being the greatest in the swan.'* As the tail of the Plesiosaurus was short, and the neck long, its form was the converse of that of the Ichthyosaurus, and the views of Geoffroy de St. Hilaire,' says Mr. Conybeare, that nature, in the organization of the animal frame, has caused the sternal portion to shift its position along the vertebral column, seem to derive an important corroboration from the structure of this animal-; but it is remarkable that whereas the sternum holds a mean position in quadrupeds, and is thrown forwards in fishes, and backwards in birds, yet its position in this instance assimilates the Plesiosaurus less to fishes, though destined to move in the same element, than to birds, and exhibits at the same time a very wide departure from the type of the Saurian tribe.' · From the smallness of its head, its length of neck and shortness of tail, the Plesiosaurus, although it wanted a shell, was in some degree analogous in its general proportions to the tortoise and turtle-- the latter it must have resembled in its motion.

• That it was aquatic is evident from the form of its paddles; that it was marine is almost equally so from the remains with which it is universally associated; that it may have occasionally visited the shore, the resemblance of its extremities to those of the turtle may lead us to conjecture ; its motion, however, must have been very awkward on land ; its song neck must have impeded its progress through the water, presenting a striking contrast to the organization which so admirably fits the Iclithyosaurus to cut through the waves. May it not therefore be concluded (since, in addition to these circumstances, its respiration must have required frequent access of air) that it swam upon or vear the surface, arching back its long neck like the swan, and occasionally darting it down at the fish which happened to float within its reach ?'--p. 388.

The habits here ascribed by Mr. Conybeare to the Plesiosaurus correspond very closely with those of the Testudo ferox, an inhabitant of Pensylvania, Carolina, and East Florida, whose neck when extended is nearly equal to its shell in length. It is described in Shaw's Zoology, as · fond of the muddy parts of rivers, hiding itself among the roots and leaves of water-plants, and thence springing on its prey, stretching out its neck to an incredible length, and seizing with celerity birds, &c. A restoration of the skeleton of the Plesiosaurus dolichodeirus, and another of that of the Ichthyosaurus communis, are given by Mr. Conybeare. We need say nothing of the discernment and anatomical skill with which these tasks have been performed; it is only necessary to mention that M. Cuvier, by adopting in almost every particular, and after a full examination, in his Fossil OsPage 383.

+ Vol. iii. p. 63, 60.

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whether it might not be proper to commit to competent persons the task of examining this part of our law, with a view to determining if any improvement can safely be made in it, which might lessen the expense and parrow the field of litigation respecting the transfer of property?

The recommendation contained in this passage of the Report is indeed conveyed in terms which are framed with all the caution to be expected from persons in the exercise of so high and responsible an office, when speaking on a subject not strictly within the scope of the inquiry committed to them, however incidentally connected with its objects. But it is impossible for the most superficial reasoner not to perceive the extent of meaning couched beneath the guarded expressions which they have employed, and in which sense they seem to have been considered by Lord Redesdale himself where he signifies his full approbation of this part of their suggestions. What (it must be asked) is the law of Conveyancing, the niceties and subtleties of which give rise to so many questions, the origin themselves of suits so complicated and protracted, but the whole system of jurisprudence by which the transmission of property from person to person is governed; and how can any investigation of the subject be limited, so as not to embrace that entire system, and the very principles on which it is founded?

Scarcely had these intimations been given, when they were answered by a work of singular novelty, both in its exhibition of the system itself, so far as regards the subject of real property, and in suggestions for its amelioration. Embracing, as does the work alluded to, the entire subject which it professes to discuss, its copiousness and, at the same time, its severe compression, alike forbid the supposition of its being the mere production of the moment; and we are forced to conclude that, by a fortunate coincidence, the author was already prepared for the enterprize in which the sudden demand of the occasion induced him, perhaps, more immediately to embark.

Mr. Humphreys, a gentleman well known for his professional skill and experience, (qualities which cannot fail to add weight to his theories, and force to the confidence which we are disposed to place in his reasoning,) commences the work which we are about to consider, with a distinction, hitherto unremarked by us, between political and civil institutions, as regarded with a view to correction. The former, he observes, are in their nature comparatively simple, and they affect the great body of the people.

When a government possesses the elements, and a people the character of freedom, it is by the quick perception and the energies of the public that political defects are detected or abuses remedied; and, in


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