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REMAINS OF FISHES.

Teeth of squali, &c. in Speeton clay, coralline oolite, &c.
Head and scales of unknown fishes, lias.
Radius of a balistes ? lias.

REMAINS OF REPTILES.

Crocodile, in coralline oolite and lias.
Ichthyosaurus, in Speeton clay, coralline oolite, and lias.
Plesiosaurus, in Bath colite.
Undescribed

genus,

in lias.

FOSSILS OF THE DILUVIUM,

IN THE EASTERN PART OF YORKSHIRE.

The organic remains found in diluvium must be divided into two groups; viz. those which, having been at some former period enclosed in solid strata, were transported from their original sites by the violence of the deluge, and those which belonged to animals living immediately before that catastrophe. Of the former kinds, we find on the Yorkshire coast and in the vales of York and Cleveland, a great variety, transported in different distances and in different directions. A considerable number of them are described in Mr. Kendall's “Catalogue of Scarborough Minerals and Fossils." Amongst those derived from the mountain limestone of Yorkshire, we may notice a beautiful retepora and a millepora, both nondescript; tubipora strues, Linn.; catenipora catenulata, (chain coral,) a beautiful favosites, and several species of astræa, caryophyllia, and turbinolia, besides spiriferæ, productæ, terebratulæ, and crinoïdal columns. From the coal districts of western Yorkshire, we have lepidodendra and variolariæ. But the most abundant diluvial fossils on the coast, are those derived from the lias cliffs in the north ; for it is hardly too much to assert that three-fourths of the fossil shells of that stratum may be found in its bouldered fragments between Scarborough and Hornsea. Few of the numerous fossils of the oolitic formations occur in the diluvium, and no belemnites nor inocerami of the chalk have been carried by the deluge to the northward, though they are often found in the cliffs of Holderness.

The organic remains of the second group,-viz. of animals which lived on the earth immediately before the flood, are neither so numerous nor so various as the preceding. Those found in the gravel and clay of Yorkshire, consist of the tusks and molar teeth of elephant, and teeth and bones of horse, ox, and deer. But the osseous remains of many other animals were found in the celebrated cave of Kirkdale, near Kirkbymoorside, so well preserved as to allow of their species being perfectly determined. The interesting phenomena of this cavern have been so ably unfolded by Dr. Buckland in his · Reliquiæ Diluvianæ,' that I determined from the first to refer to that admirable work for descriptions and figures, which could not be introduced into mine without greatly enhancing the price. I was, therefore, unable to avail myself of the generous offer of Mr. Salmond to supply me with original information from his own valuable and instructive description of the cave which he explored with so much zeal and success.

The teeth and bones discovered in this cave belong to the following species of animals;

7. Carnivora ; hyæna, tiger, bear, wolf, fox, Weasel, and, according to Mr. Salmond, lion.

4. Pachydermata ; elephant, rhinoceros, hippopotamus, and horse.
4. Ruminantia; ox, and three species of deer.
4. Rodentia ; hare, rabbit, water-rat, and mouse.
5. Birds ; raven, pigeon, lark, duck, and partridge.

The floor of the cave was covered with sandy mud ; on this lay an irregular deposit of stalagmite, produced by droppings from the roof which was studded with pendent stalactite, and by currents down the sides of the cavity, which were also partially lined with the same cal

A a

careous incrustation. The bones lay dispersed in the mud and in the stalagmitic crust, broken into angular fragments and chips, but not “ bearing the least appearance of having been rolled in water ; nor was a single pebble found in the cave.” The fractures appeared all to have been occasioned by violence, and many of the fragments were marked with impressions, such as a living hyæna has been found to imprint on similar bones submitted to his powerful jaws. These circumstances, combined with the evidence derived from the album græcum, and the extraordinary number of teeth of hyænas, in every condition from that of the milk-tooth to the aged grinder worn to the gums by mastication, seem to fully justify Dr. Buckland's opinion that this was a den of hyænas who dragged into it piecemeal the other animals, for food.

The quantity of the reliquiæ seems to shew that the cave was tenanted for a long succession of years; and a comparison of these remains with others found in diluvial gravel, determines that they belong to the same extinct species. As there is no evidence that such animals have existed in this country (or, indeed, in any part of the world) since the flood, the only conclusion at present tenable, is, that the cave was an antediluvian den, of the same nature as Kent's hole, and the bear caves of Franconia. We must, therefore, admit that before the deluge, this country was inhabited by a variety of animals which now dwell only in tropical regions, and the question of its ancient condition is answered in one of its terms. We

may

further infer, that, since its inhabitants were analogous to those that now exist, its surface had the same general characters ; forests for the stag and the elephant, lakes for the rhinoceros and the hippopotamus, and rocky coverts for the prowling hyæna. These animals might be fitted by constitution to support the rigours of a northern climate ; but the general harmony of geological phenomena seems to be better preserved by admitting that the northern regions of the earth were warmer before the flood, than at present.

CHAPTER V.

On the Basaltic Dyke.-On the economical Uses of the Mineral Pro

ducts in the Eastern part of Yorkshire.

One of the most remarkable features on a geological map of England is the line of the great trap dyke from beyond Cockfield fell in Durham, to the Sneaton moors in Yorkshire, a distance of sixty miles. That this subterranean wall of basalt is really connected through the whole of this length, few will be inclined to dispute, who have studied the character of the rock, and observed its bearings at Cockfield fell, Bolam, Langbargh, and Lilhoue cross, but it is not traceable between all these points on the surface of the ground. It is a common opinion, that this dyke is united, toward the west, with the “ great whin sill,” or basaltic formation of Upper Teesdale, and certainly in appearance and composition they much resemble each other. On the east it does not reach the sea side, but terminates obscurely, after crossing near its source the easternmost branch of Littlebeck. Its general direction is E. S. E. and W. N. W.; but in several places considerable deviations in this respect are observable. The breadth is commonly about sixty feet, as at Cockfield fell, Langbargh quarry, and Egton ; but it diminishes to less than thirty feet at the eastern extremity. At Bolam in Durham, it expands into a large pyriform mass, having the appearance of an interposed vein, resting on black shale. The sides of the dyke are seldom perpendicular, but generally slope downwards toward the north. At Langbargh quarry this slope is about 1 in 8. The strata through which the dyke passes are generally dislocated, so that a given layer is found considerably higher on the south side than on the north.

As might be expected, this hard rock has been less wasted by the deluge and the changes of the atmosphere, than the softer strata which bound it, and, therefore, in some places it appears above them in a long crust or ridge. On Clifton rigg its blocks, lying bare on the surface, have been compared to prostrate pilasters half buried in ruins ; near Egton bridge it stands up in a lofty wall, over the waters of the Esk; and beyond Lilhoue cross, it ranges along the moors like an ancient military road; but in a large portion of its range, especially in the wide vale of Tees, it is concealed by diluvial accumulations.

The composition of the basalt presents few peculiarities. Olivine, calcareous spar and quartz are the principal extraneous minerals. Hollow geodes occur in it, of which the walls are amethystine quartz, presenting crystalline facets to the cavity which contains a crystal of carbonate of lime. The joints, which are often lined by a sooty substance, are in most quarries irregular, and lie in all directions; but sometimes a tendency may be noticed to the horizontal prismatic structure, which prevails in narrower dykes of the same substance in the island of Arran. At Bolam, in Durham, where the mass extends itself more horizontally, the pseudoprisms approach to a vertical position. Thin, flexuous, irregular, nearly horizontal layers of basalt appear in Langbargh quarry, and decomposing balls, with ochry outsides, are common.

The following strata are divided by this remarkable dyke; viz. mountain limestone ; sandstone, shale, and coal; new red sandstone and red marl; lias shale, &c. and the lower sandstones of the oolitic series. These strata, where they come in contact with the basalt, are more or less altered in appearance and composition, and the change seems generally due to the action of heat. At Cockfield fell, the coal near the dyke is converted to a black substance like concreted soot, and at a small distance changed to a cinder without bitumen or sulphur, and beyond, gradually regains its usual properties. “ In the stratum above the cinder a great deal of sulphur is sometimes found, in angular forms, of a bright yellow colour, and very beautiful."* “ At Berwick on the Tees, the

* Mr. D. Tuke, in a communication to the Yorkshire Philosophical Society.

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