and a few of the teeth only having been preserved, Mr. Montagu's description is very imperfect: but, if we might hazard a conjecture grounded on his cautious observations, we should be tempted to pronounce the specimen in question to be synonymous with the Delphinus Rostratus of Cuvier, as described in the 19th volume of the Annales du Muséum. We concur, however, with the late venerable author in the remark that much obscurity still hangs over the history of the Delphini; and systematical writers have, perhaps, laid too much stress on the number and characters of the teeth, which seem liable to vary even in individuals of the same species.

Observations on the Mineralogy of the Neighbourhood of Cork. By the Rev. John Fleming, D.D., &c. These annotations apply to the greywacké, lime-stone, and clay-slate strata, with their subordinate members, constituting a series of transition-formation in the south of Ireland. In the greywacké, or, as some would term it, sand-stone of the independent coal-formation, are found impressions of certain dicotyledonous plants, and in some places bivalve shells, but too much incorporated with the rock to exhibit their peculiar characters. The lime-stone, which is universally used for building, and is sometimes polished as a marble, includes various remains of testaceous mollusca, several of which have been figured and described by Sowerby, in his Mineral Conchology. Subordinate to this compact lime-stone, and in the form of a thick bed, or of large irregularly shaped masses, occurs common compact dolomite, or magnesian lime-stone, containing groups of crystals of brown or pearl spar, quartz, &c. In some of the larger druses, crystals of amethyst have been found of considerable size and beauty. Some of these have exceeded two inches in diameter, and four inches in length. In one place, close by the marshy banks of the river, and near the town, the best crystals have been found; but in consequence of a dispute between the King and the proprietor of the soil, with respect to the right of search, all access to the cavity is prevented.' The rocks of clay-slate are situated to the south of the preceding, and, though variable in texture and aspect, occasionally afford- quarries for roofing slate, black chalk, and wavellite. This last-mentioned mineral substance, which is somewhat rare, was pointed out and described by Dr. Fitton; and Dr. Fleming has added a few particulars: but he entreats the indulgence of the Society towards his hurried survey, being aware that they do not attach much value to mail-coach mineralogical observations.' The rapidity of Irish driving seems even to have jostled his associations of noun and verb into an unconformable condition;

as,

as, for example, Neither this oval form, nor the oblique position of the valves of the terebratulæ, arise from any bruise, but is quite natural.' The character of the rocks are well exhibited.' The appearances which the wavellite of this place exhibit,' &c.

Mineralogical Notices and Observations. By the Rev. Thomas Macknight, D. D.-These memoranda will prove serviceable to the geological traveller who may be desirous of making the grand tour of the Scotish Highlands, by indicating various interesting localities of the primitive formations; such as the junctions of the granite and gneiss, the slate-repository of Balahulish, the rocks which overlie the great mica-slate formation, &c. Of Cairngouram, more commonly written and pronounced Cairngoram, producing a stone now used for seals and other purposes, the ensuing particulars may not be unacceptable even to the general reader :

The great mass of this magnificent and extensive range, whose summit appears little inferior to Ben-Nevis in height, is composed of granite, in general uncovered with soil, and unaccompanied with other rocks; but containing a rich store of the precious stones, so well known by the name of the mountain, where they are found in veins and drusy cavities, associated chiefly with rock-crystal: of which, indeed, for the most part, they are only varieties of different colours, as yellowish-white, clovebrown, or brownish-black, &c. Accordingly, in traversing this range, for a considerable distance, I had an opportunity of verifying Professor Jameson's conjecture respecting the original repository of the Scotch topaz. I was shewn a number of places, where the crystals had been extracted from the rock by means of blowing and the pick-axe, &c.; and could observe many openings in the rocky fronts, where, if at all accessible, the adventurous searcher would, it is likely, find his labour and risk amply repaid, by valuable treasures of the same kind.

*

The

We can, therefore, now easily understand, how the topaz of Aberdeenshire (for a particular description of which I must refer to Mr. Jameson's paper already quoted) has so often been found, as well as amethyst, and precious beryl, in the alluvial soil. fact, however, I believe, is, that by far the greater number of these gems are gathered among the debris of the granite rocks, in the beds or ravines of the small streams which issue from the mountains in this district. Those who employ themselves in searching for the stones pay the proprietors a small rent for the liberty of searching. The part of the range which lies to the east, and is called Ben-Aven, is at present reckoned the most productive; yielding the proprietor, I was told, about 150l. or 2007. a-year. What is properly called Cairngouram, opposite to Aviemore, and skirted on the north by the extensive woods of Rothie

* Wernerian Memoirs, vol. ii. p. 452.'

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murchus,

murchus, has now been so completely stripped of its products in the ordinary track of examination, that a mere traveller, limited in time, has little chance of meeting with specimens of much value; but the people in the neighbourhood have always a number to offer for sale.

The granite of Cairngouram consists chiefly of quartz and felspar, both compact and crystallized; the mica occurs but sparingly. In some places, the materials of the rock appear to be disposed in layers or strata; almost horizontal. I remarked, that, perhaps, there are few instances in which a mineral substance, spread over so great an extent of surface, exhibits so little variety of oryctognostic character, as the granite of this range. Specimens collected at the distance of several miles can often scarcely be distinguished from each other, by the nature or appearance of their constituent parts. If the zealous mineralogist could submit to spend days in traversing the dreary untrodden regions and to pass his nights among the bare rocks of Cairngouram, there is little doubt that his toil and patience would be rewarded, by the discovery of many valuable gems and curious minerals.'

Additional Observations on the Coal-Field of Clackmannanshire, and a Description of the absolute Shape or Form of the Coal-Fields in Great Britain. By Robert Bald, F.R.S. E. &c. Many of these statements will be best understood by references to the plates: but others require no such illustration; and they all derive importance from the nature of the subject, and from the consideration of their practical usefulness, or from the curious information which they convey.

Of the antient and the more recent beds of alluvial matter, which form the uppermost strata of the Clackmannanshire coal-field, it is not a little remarkable that the former, which is the most elevated, and nearest to the hills, is destitute of organic remains, although the coal immediately under it exhibits them in abundance, as do the later alluvia of the Forth and Devon. It is also worthy of notice that the older deposition, which is of a very miscellaneous character, being composed of clay, sand, large smooth and rounded stones, and gravel, involves fragments of all the strata found in the coalfield, but preserving their sharp angles, and bearing no marks of attrition, although of a comparatively soft texture. These alluvial investments are of very various depths, from a few inches to many fathoms. In the more recent coverings, are found trunks and branches of large trees; beds of sand, containing sea-shells, particularly a variety of oyster much larger than any now known to exist in the Forth; horns of the stag; and large bones, probably belonging to some of the cetaceous animals:

There is one remark regarding the stratification deserving particular attention, which is, that the immediate stratum or pave

ment

ment on which the beds of coal rest, is almost without exception a greyish-black rock or fire-clay, which, when made into bricks, strongly resists the effects of fire. This fire-clay is found from the thickness of the tenth of an inch to several fathoms. In no instance have I seen the coal incline to contact with any other of the strata, excepting where the coal was intersected with numerous slips and dislocations: and this particular observation I have found to hold, in all the coal-fields I have examined in Great Britain. When this fire-clay is of any considerable thickness, it abounds with the remains of the vegetable kingdom, with a few kidneyshaped pieces of clay-iron-stone.'

The partings, as they are technically called, or foliaceous dissepiments, which mark the separation of the various strata, usually consist of clay, or sand. Having defined the bearings and accidents of the coal-strata of the Clackmannan district, and particularly their saddle or mantle-shaped disposition, Mr. Bald adverts to the prevalence of red sand-stone in the field; which, as it has by some been mistaken for the old red sand-stone of the Wernerians, he terms blush-coloured.

As the following rule may prove of essential service to coalminers in general, we give it all the publicity of our circulation

With regard to slips in coal-fields, we find that there is a general law connected with them as to the position of the dislocated strata, which is this: when a slip is met with in the course of working the mines, if, when looking at it, the vertical line of the slip or fissure forms an acute angle with the line of the pavement upon which the observer stands, we are certain that the strata are dislocated, or thrown downwards upon the other side of the fissure. When the angle is 90°, or a right angle, it is altogether uncertain whether the dislocation throws up or down on the opposite side of the slip. When dikes intersect the strata, they generally only separate the strata the width of the dike, without any dislocation either up or down; so that if a coal is intercepted by a dike, it is found again, by running a mine directly forward, corresponding to the angle or inclination of the coal with the horizon.'

In the remarkable coal-field at Johnstone, near Paisley, the upper stratum of rock is compact green-stone, more than 100 feet in thickness; and this is followed by a few fathoms of alternating and soft sand-stone and clay: under which, in one place, are not fewer than ten beds of coal, lying immediately above one another, with a few thin divisions of darkcoloured indurated clay. These coal-beds are 100 feet in thickness, presenting a mass of combustible matter which is scarcely paralleled in the annals of mining.

At Brora, in the county of Sutherland, the coal is completely insulated, and borders on mountains of red granite,

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lying

lying under a few beds of dark-coloured slate-clay, ferruginous lime-stone, and indurated clay, mixed with lime and limestones; including a profusion of organic remains, particularly large cornua ammonis, belemnites, bivalve shells, and fossil wood. The coal, in burning, emits the odour of rotten wood. Another peculiarity in the history of our coal-fields is a stratum of thirty feet thick, at the Castle-hill, near Dudley, in Staffordshire; where the coal strata exhibit an example of the inverted basin-shape, the reverse of the general position, which is more or less that of a regular basin, or segments of

that form.

-

Account of some Sand-stone Petrifactions found near Edinburgh. By the Rev. James Grierson, M.D. Dr. G. here describes three fragments of trunks of trees, the largest of which measured three feet ten inches in circumference, at its thickest extremity: but they do not materially differ from numerous other specimens that might be quoted. The author ingeniously attempts to account for their origin on the principle of the chemical solution of the siliceous particles, and the escape of the vegetable elements in a gaseous form; and this view of the subject, as we have more than once hinted, is at least as conceivable as the ordinary doctrine of the mechanical substitution of the mineral for the vegetable molecules, although this last is sanctioned by the weighty and venerable name of Haüy:-now, alas! no longer a living name.

Description of the Simia Sagulata, or, Jacketed Monkey. By Dr. Traill.-The specific characters of this addition to the catalogue of Simiæ are, head black and bearded; tail not prehensile, thickly set with black hairs, claviform; body below black; back well clothed with an ochry-coloured fur.' The general aspect of the animal somewhat resembles that of S. Beelzebub, or the Preacher Monkey: but the form of the tail and the colouring of the upper parts are different. It is a native of the forests of Demarara. Nothing is said of its

manners.

Description of a New Species of Felis from Guyana. By the Same. This is another non-descript quadruped, from the same region of the world, and has been denominated Felis Unicolor, or Spotless Cat, from the uniformity of its colour. Its specific definition is, Cat with a long tail; the whole body spotless, and of a clear reddish-brown colour.' general appearance it approaches to the Puma; from which, however, it differs in various respects. It resides in the deep recesses of the forests, climbs trees to prey on birds, monkeys, &c., and will even boldly attack the large quadrupeds.

In