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strata have been penetrated to 214 feet below sea-level without finding rock-salt. The brine rises there to a height of about 130 feet above sea-level; whilst at Winsford rock-salt beds, similar (as far as worked) to those at Northwich, occur at a depth to the upper bed of from 90 to 120 feet below sea-level. The brine rises there to a height of about twenty-five feet above sea-level. The line thence passes into Staffordshire, near Whitmore.

A fault ranging from south-west to north-east, passes by the north-west of the Peckforton hills across Delamere Forest, by the north-west of Northwich, dividing that salt from the easterly ends of the Waterstone, or lower beds of the keuper, and thence to the east of Timperley. The north-east boundary of the Northwich salt was not determined. The south-east is formed by a line parallel to the north-west side, about 1300 yards distant therefrom.

Within this area frequent subsidences of the land take place. From this cause the locks on and the banks of the Weever have been here raised. The land where a factory stood, near Northwich-bridge, has sunk so as to form a wharf. A few years since, the subsidence near the junction of Whitton-brook and the Weever was at the rate of three inches per week at this point a lake is now rapidly forming. The salt pans at the works by the Weever have been frequently raised, and many are now abandoned. The course of Whitton-brook, which in 1811 was made six feet deep, now varies in depth from ten to thirty feet. About two miles to the north of Northwich, near the north-western boundary fault, some fields are sinking. In this area the brine stands at the same level, and varies simultaneously in all the pits. That the rock-salt of Northwich does not extend beyond the above limits, is further shown by the fact, that the neighbouring ground beyond the above boundary lines does not sink, and the brine where found beyond the said boundary is reached and stands at various levels-all differing from that at Northwich.

Minute descriptions of the salt, and the methods of working the same being given in various well-known works, the same were not here noticed.

Notice of the Coal of India, being an Analysis of a Report communicated to the Indian Government on this subject. By Prof. ANSTED, M.A., F.R.S. &c.

The coal districts of India may be considered as five in number,-three in Northern India and one in Cutch, whilst the fifth includes the province of Arracan and the coast of the Birman empire near Tenasserim. Of these the Cutch coal is certainly not of the carboniferous epoch, and it appears to be of little importance at present and unpromising.

The whole district, extending from the neighbourhood of Hoosungabad on the Nerbudda river (lat. 23° N. long. 78° E.), on the left or south bank of the river, and extending in a north-easterly direction for a distance of about 400 miles to Palamow, thence eastward, for 250 miles, to Burdwan, near Calcutta, and running northward, for 150 miles, to Rajmahal, exhibits, it would appear, at intervals by no means distant, a continually repeated outcrop of rocks, consisting of sandstones and shales, with occasional limestone. Throughout this wide tract a number of beds of coal have been recognised, of variable thickness and value, but all appearing to exhibit evidence of the existence there of a great coal-district.

On the flanks of the Garrow Mountains, near the Burhampooter, and on both banks of that vast river, we find another, perhaps a continued outcrop of similar beds, also containing coal, and reaching in a north-easterly direction for nearly 400 miles. The intermediate plains, whose breadth between Rajmahal and Jumalpore is about 100 miles, are chiefly alluvial, and thus it is possible that there exists a vast range of carboniferous strata, reaching for upwards of 1000 miles along the flanks of the Himalaya Mountains, the distance from the mountain chain gradually increasing as we advance westward, the mountains trending northwards and the outcrop of the carboniferous bed southwards, until finally, the distance between them being upwards of 500 miles, the relation is not easily recognised.

I. Commencing with the neighbourhood of Calcutta, we have first to consider the Burdwan coal-district, with which I shall group the Adji and the Rajmahal fields, all these being on the banks of either the Hooghley or Ganges, or on the tributaries of these rivers. The Burdwan district has been long known, and a good

deal worked. The workable beds of coal are nine and seven feet thick respectively. They are associated with sandstone, shale, and a little clay-ironstone, and about six other thinner seams of coal, while other thick beds are mentioned, but their real existence as separate beds is doubtful. There are now thirteen spots at which this coal is worked, but most of them are surface workings. The deepest sinking is 190 feet. The distance to Calcutta is about ninety miles, but the actual transit of coal is nearly 200 miles. There would seem to be a continuous outcrop of the same kind of rocks from Burdwan up the Adji river, and northwards to Rajmahal. On the Adji river the coal has been worked in more than one spot, and is found to be of about the same quality as that of Burdwan; but neither of them is considered of nearly so good quality as the English coal. Further on, at Rajmahal, coal is known to exist, but has not yet been much worked. The quality of that which has been obtained does not appear good.

II. The Burdwan coal-field appears to be directly connected with a district at Palamow, in which coal has been worked in no fewer than four places. The coal here apparently reposes in a valley inclosed by hills of granite, and is associated with a good deal of iron. There are several beds that are of workable size, but a good deal of the coal is heavy and of inferior quality, and some of it appears to be anthracitic. These coal-beds are not far from the Soane river, and about 100 miles from its confluence with the Ganges, a little above Dinapoor and Patna; but the Soane is not at present navigable. To the west of Palamow the carboniferous beds are described as appearing along two irregular lines, the one towards the south-west for 150 miles, reaching beyond Koorbah, and the other more westward, by Sohagepoor, to the Nerbudda. These beds appear to connect themselves with the Burdwan coal-field; and near Ramgurh coal has been obtained in two or three places. This coal is said to be of very good quality and of considerable thickness; but there can be little doubt that a statement made in the report, of the bed of coal being 200 yards in thickness, must be owing to some misunderstanding of the account and sketch originally communicated. It seems certain, however, from the extent of the outcrop, that the seam must be one of considerable magnitude. Westwards, again, from Palamow, and at a distance of about fifty miles, coal has been found in several places in Singrowli, but the beds at present known are thin; and again, to the south-west, the same mineral occurs at Sirgoojah, where fine coal has been seen, but is not used at present. Between the Singrowli coal and Jubbulpore excellent coal has been found in several places, indicating an extensive coal-field; but the nature and thickness of the beds are not stated.

The Nerbudda district, although from the drainage of the country it belongs to the Bombay side of India, is manifestly more related, so far as the old rocks are concerned, with the Bengal territory. The coal is about 350 miles from Bombay, and the Nerbudda river is at present not navigable. There seem to be three districts in the Nerbudda valley in which coal is found, but the most important of them is that near Gurrawarra, about midway between Hoosungabad and Jubbulpore. The coal here, indeed, appears to be perhaps the best hitherto found in India, and exists in beds three in number, whose thickness respectively is said to be 20 feet, 40 feet, and 25 feet. There are also other beds, one of which is four feet.

The discovery of this, the Benar coal-field, promises to be of great importance. It is also very near another basin, where there are beds also of excellent quality, one of them six feet in thickness. At Jubbulpore itself coal has been found at a depth of seventy feet, one bed being nearly twelve feet thick.

III. Let us consider now the district east of Calcutta. We there find true carboniferous rocks on both flanks of the Garrow mountains, commencing near Jumalpore, and thence continuing north-eastwards, for a distance amounting on the whole to nearly 400 miles, through Lower and Upper Assam. The district nearest Calcutta is Silhet, on the south flanks of the Garrow, where eleven beds of coal have been determined, whose total thickness as already ascertained amounts to eighty-five feet. This coal is of excellent quality, and can as readily be conveyed to the Upper Ganges as the Burdwan coal. The most remarkable beds occur at Cherra Ponji; but these appear irregular, although they are undoubtedly of great thickness in several spots, amounting sometimes to nearly thirty feet. There are also other important beds. They have been known for more than ten years, but have not been

worked; and since their first discovery large quantities of iron have been smelted with charcoal.

After passing the districts in which the coal has been thus clearly exhibited, we proceed next to the Assam districts, also more or less continuous, and extending for about 350 miles chiefly along the south side of the Burhampooter; the whole being divided into the two groups of Lower and Upper Assam, separated at Bishenath, 170 miles above Calcutta. Six coal-fields are enumerated in the Upper district, and three in the Lower; but the latter, although it would seem not so promising, are looked on as scarcely less important in consequence of their greater accessibility.

So far as details are concerned, the Lower Assam coal offers little positive information; the indications consisting rather of rolled fragments drifted, than of distinct and well-marked beds. It is called lignite in a report from Lieut. Vetch; but both coal and lignite are terms frequently used without reference to any peculiar character of the mineral, or any geological position. Similar beds of coal or lignite to those found in Lower Assam, south of the Burhampooter, are also mentioned as occurring on the north in three of the streams flowing into that river from the Bootan range. The Upper Assam coal is manifestly of great interest, and likely to prove very important. It is associated with abundance of clay ironstone.

About eighty miles above Bishenath, other beds, stated to be six feet thick, have been worked for the sake of trying the œconomic value of the coal. It is described by the commander of one of the Assam Company's steamers, in a letter dated 24th January, 1845, as far the best he ever had on board a steamer, and far superior to any coal in Calcutta. From the growing importance of the tea-trade from Assam, this is likely, therefore, to be of great value. Still further up the country there are several important beds, dipping, it would appear, at so high an angle, and placed so unfavourably with regard to present means of transport, that it would be difficult to work them. The other beds that appear in this district are exposed to the same difficulty; and the coal throughout Northern India appears to be in this respect unfavourably placed.

Passing on now to the other districts in India and the East, in which carboniferous rocks and beds of coal have been met with, I have to enumerate two, the Tenasserim and the Arracan districts, which, from their vicinity to India and their geographical position, are of considerable importance. The former has been known for some years, and there are said to be four localities at which coal appears; but of these only one seems likely to prove of œconomic value. From the accounts given of this coal there is every reason to conclude, that one of the beds is not of the carboniferous period; and although another (on the Thian Khan) has been the subject of a far more favourable report, being called cannel coal, and stated by Mr. Prinsep to be an admirable coal for gas, there is yet much probability of the whole being of the tertiary period. These beds have been described in the Journal of the Asiatic Society' for 1838.

In Arracan there are eleven beds of coal, but all of them are thin, and their position nearly vertical. They are said to be associated with sandstones, limestones and shales; but it is clear that they can at present be looked at only as indications, and not of any practical importance.

Notices of some Fossil Mammalia of South America. By Prof. OWEN, F.R.S. Since the publication of his descriptions of the fossil mammalia collected by Mr. Darwin, the following additional species had come under observation. A new species of the gliriform genus of Pachyderms called Toxodon, was founded on an entire lower jaw, with the intermaxillary part of the upper jaw of a specimen equalling the Toxodon platensis in size, transmitted from Buenos Ayres. The new species, which Prof. Owen proposed to call Toxodon angustidens, is distinguished by the nearly equal size of the outer and inner incisors of the upper jaw, the transverse diameter of the inner or median one being two inches; and by the narrower transverse diameter of the inferior molars. Prof. Owen considered the characters of this second species of Toxodon as confirming in every respect his ideas of the affinities of the genus expressed by the title, 'Description of the cranium of the Toxodon platensis, a gigantic extinct mammiferous animal, referable to the order Pachydermata, but with affinities to the Rodentia, Edentata, and herbivorous Cetacea,' under which his original me1846.

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moir was published in 1838. M. Quatrefages, in his 'Considérations sur les Caractères Zoologiques des Rongeurs,' 4to, 1840, had corrected what he assumed to have been Prof. Owen's allocation of the Toxodon to the Rodent order. M. Quatrefages thought the so-called incisors of the Toxodon to be canines, affirming that their roots extended to the maxillary bones above the first molars; and he regards the Toxodon as having a nearer affinity to the Morse (Trichecus). Prof. Owen referred to his 'Odontography,' p. 411, for a refutation of Geoffroy St. Hilaire's ideas that the scalpriform incisors of Rodents were canines; and alluded to the enamelled complex molars of the Toxodon as opposing M. Quatrefages' idea of its relationship to Trichecus.

An almost entire skull of the Mastodon Andium had been transmitted to the British Museum from the post-pleiocene beds of the Pampas of Buenos Ayres; its molar dentition was described, and a distinctive character of its tusks, in a strip of enamel two inches broad along their outer sides, was pointed out.

Macrauchenia. To this genus of tridactyle Pachyderms, which is nearly allied to the Palæotherium by the structure of the feet, and to the Llamas (Auchenia) in the structure of the neck, Prof. Owen had referred a molar tooth of the lower jaw (No. 952, Mus. Coll. Chir), on account of its crown being composed of two upright half cylinders of equal height, as in the Palæotherium. A left ramus of the lower jaw, from the tertiary deposits of Buenos Ayres, has been received, containing six molar teeth, three true and three false, the last four showing the same form or pattern as the single fossil tooth from Patagonia, demonstrating the resemblance with the lower molar teeth of the Palæothere, except in this difference, viz. the absence of the third lobe in the last molar, by which the generic distinction of the South American Pachyderm was established; and an approach made to the rhinoceros, The Ma, crauchenia, to which Prof. Owen provisionally referred the fossil in question, differed however, like the Palæothere, from the Rhinoceros, in the greater exterior convexity and equal height of the two semi-cylindrical lobes of which the last premolar and the three true molars were composed; and it further differed from both Palæothere and Rhinoceros in the more simple form of the second and third premolars; the enamel is smooth and the dentine compact, and the coronal cement forms a thin layer. The longitudinal extent of the six molar teeth was nine inches.

Nesodon, n. g. A genus allied to the preceding, but resembling the Anoplotherium, in the absence of any vacant interspace in the entire dental series, and in the equal height of canines and incisors, was established on the anterior part of the lower jaw and on two molar teeth of the upper jaw, discovered by Capt. Sulivan, R.N., in an arenaceous tertiary deposit on the coast of Patagonia. The incisors, canines, and premolars of the lower jaw are not only in contact, but overlap each other like scales or tiles, and the molar teeth of both upper and lower jaw are characterized by islands of enamel, whence the generic name proposed. The incisors are six in number. The characters described by Prof. Owen show some resemblance to Toxodon, in which also the large procumbent incisors overlap each other: the interval between Toxodon and Macrauchenia is evidently partly filled by the present remarkable genus. The extent of the sloping symphysis, the breadth of the lower jaw behind the symphysis, and the depth of the ramus at the beginning of the first true molar, were severally two inches. The quadruped to which these fossils belonged must have been about the size of the Llama. Prof. Owen proposed to call the species Nesodon imbricatus, in allusion to the tile-like, overlapping arrangement of the anterior teeth. A second larger species of Nesodon was indicated by four or five detached teeth of the lower jaw from the same deposits. This species, of the size of the Zebra, it was proposed to call Nesodon Sulivani.

As a check to the undue increase of so many large herbivorous species of the Megatherioid and Pachydermal orders, the great Machairodus, discovered in the caves of Brazil by Dr. Lund, who first supposed it a hyæna, was well-adapted. An almost entire skull had been, thence, transmitted to Paris, and had been referred by M. de Blainville to the genus Felis, who had published a figure of it. A specimen of the same, or a closely allied species, displaying some characters not preserved in the Parisian specimen, had been transmitted from the tertiary deposits of Buenos Ayres. Prof. Owen pointed out several differences establishing the, at least, subgeneric distinction of this remarkable carnivore, which equalled the Bengal Tiger in size, and had upper canine teeth of thrice the length. As Prof.

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Owen could not determine any specific distinction in the present fossil from the Hyæna neogea or "Smilodon" of Dr. Lund, he proposed to call the species" Machairodus neogæus." This, happily extinct, most formidable and destructive of the carnivorous genera, had anciently an extensive geographical range through a great extent of South America, in India, and throughout Europe; fossil remains of different species having been found in old pleiocene deposits in Germany and France, in the newer pleiocene of the Val d'Arno, and in the bone-caves of England. Our own ancient Machairodus latidens of Devonshire, added to the other species, confirms the propriety of keeping the genus distinct from the typical Felis.

Of the gigantic extinct Armadilloes, Prof. Owen added to the former species, which he had called Glyptodon clavipes, the following, viz. Glyptodon reticulatus, Glyptodon ornatus, Glyptodon tuberculatus, and Glyptodon clavicaudatus. An enormous tail of the latter, now in the British Museum, showed several of the ossicles of the dermoskeletal sheath produced into huge tubercles, the whole resembling the club of the giant Gog or Magog. Prof. Owen thought that the present knowledge of the co-existence with those large herbivorous Armadilloes of a gigantic carnivorous species like Machairodus, gave some insight into their need of a complete and strong defence of all the exposed parts of the body and the tail, since they had not the powerful claws with which the Megatherioid quadrupeds might have waged war with the Machairodus. With regard to the Megatherium, the remains recently transmitted confirmed Prof. Owen's ideas of its closer affinity to the Sloths than to the Ant-eaters or Armadilloes; and had enabled him completely to reconstruct both the fore and hind extremities, and correct some errors in Cuvier's descriptions.

Mr. Edwards communicated a list of the fossils of Bracklestone Bay, Sussex. Of the classes Conchifera, Brachiopoda, and Gasteropoda, there are 161 described spe cies, and seventy-nine undescribed; seventy-four of which are also found at Barton. Of the 161 described species, 106 are identified with French and fifty-five with English species. Respecting Foraminifera, Corals, and Cephalopoda, the author states that they are under examination.

Notice of some Tertiary Rocks in the Islands stretching from Java to Timor. By J. B. JUKES, M.A., F.G.S.

Behind the town of Coupang, in the island of Timor, the land rises in gently sloping hills to the height of 500 or 600 feet, the nature of which is exposed in a narrow precipitous valley. These cliffs and the shore itself are composed of a very recent tertiary formation, which appears to be a raised coral reef, abounding in Astræa, Meandrina and Porites, with shells of Strombus, Conus, Nerita, Arca, Pecten, Venus and Lucina. On a ledge about 150 feet above the sea, Mr. Jukes found a Tridacna two feet across, bedded in the rock, with closed valves, just as he had often seen them in the barrier reefs. The thickness of this formation was proba bly several hundred feet; and it seemed to spread far and wide over the country, wrapping round the central mountains, which were lofty, and probably volcanic, peaks. Samou Island appeared to be wholly composed of this rock, often forming precipices 200 or 300 feet in height. Sandalwood Island presents a lofty coast of cliffs and hills, rising 2000 feet above the sea, and attaining a still greater elevation inland. All the coast cliffs were regularly stratified in thick horizontal beds; white when fresh broken, but weathering nearly black. The cliffs and precipices of Sumbawa are equally lofty, and exhibit the same regular bedding. The island of Lombock slopes gradually from its southern shore to a great conical volcanic mass, 11,400 feet high, which towers from its north-east corner. The southern coastcliffs, about 200 feet high, were composed of a white, horizontally-stratified rock, covered by a considerable thickness of brown and yellow thin-bedded rocks. The island of Madura was found to be composed of the same white, chalk-like strata; this island rises in one or two terraces into slightly undulating plains, with groups of flat tabular hills, often rocky and precipitous, and occasionally 1000 feet above the sea; on the opposite side of the Straits of Madura these hills continue some distance along the north coast of Java. They are wholly composed of limestone, probably tertiary; and resemble the coral rock of a fringing reef, having a similar

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