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affords much interesting scenery, and is favourable to the growth of plants which love a rocky and somewhat alpine situation. There, in particular, we find the Dwarf Cistus evolving its brilliant blossoms in the utmost profusion ;-it is the only station in Northumberland for the not less beautiful Spring Cinquefoil,-the Sea Campion, far from its shore, occasionally reappears here,-and, to omit many enumerated in the subsequent pages, the Ivy and Honeysuckle climb up the columnar rocks, decorating them with verdure and beauty, in return for the shelter and support they receive.

Let us now turn to Berwickshire ;-and of it I feel happy in being able to lay before my readers a very interesting and valuable geological outline, the essay of a much esteemed friend, and the first attempt which has been made to sketch the struc. ture of this county *.

* As an Introduction to this Essay, my friend has remarked, that " the geographical distribution of plants, their characters, habits, appearances, &c. at different elevations, and the general relation which these bear to the soil, the mineral substances, and general rock formations of the county, or district where they grow, are undoubtedly to be regarded as among the most interesting, as well as important, researches connected with the study of Botany. But until lately, these are views which have been but little attended to; botanists having been, and still being, too apt to have their thoughts entirely confined to an acquaintance with the plant itself, to the exclusion of any information connected with it,-to content themselves with merely knowing names, number of species, the place these hold in the system, &c.-and to flatter themselves, that if they have succeeded thus far, this is all that is necessary to form a botanist. Whereas, did they view the matter rightly, they would find, that so far from these summing up all that is necessary to be known in botany, they form, in fact, by far the least interesting and important parts of it,-they are little better than the mere elements of the science,the mere stepping-stones by which to arrive at its real usefulness and importance, the rude materials (very necessary, indeed, to possess), but which, un

"Berwickshire is naturally divided into two great districts, well marked by their difference of external character and surface, the High and the Low ;-the former comprehending the subalpine districts of Lammermuir and Lauderdale, the latter, which, in an economical point of view at least, is by far the most valuable, as well as beautiful, being named the Merse. The former division forms part of that great hilly range, extending in a S. W. direction from St Abb's Head to the Solway Frith, a range which, in different parts of its course, is known under different names, but every where marked by the same great features,the round-backed shape of the hills, their smooth and unbroken outline, and the thick covering of verdure, which in general reaches to their summits. The latter division again extends from the base of this hilly tract to the banks of the Tweed, which forms the southern boundary, being generally a level, smooth, unvarying extent of country, without any very marked or striking features, save those peculiar to a fertile and well cultivated district.

"Conformably to this great natural division into high and low country, the geology of Berwickshire, in a general point of view, may, in like manner, be regarded as possessed of only two grand features, and as consisting (principally at least) of only two great rock formations, of very different eras, however, and characters. These are the transition and secondary classes of rocks, the former being those which predominate in the districts of Lauderdale and Lammermuir; the latter, under the form of the second, or new red sandstone formation, being those of which by far the greater part of the Merse is composed. We

less made proper use of, will never lead to any results, either generally interesting, or generally valuable."

have said that these are the principal rocks which we meet with in Berwickshire, for we may now remark, that they are not the only ones, another distinct formation making its appearance in several different places. This, the first, or old red sandstone formation, forming the usual connecting link between the tran. sition and secondary rocks, we meet with in the south-west corner of the county, as at Dryburgh, Merton, &c. There it succeeds immediately to transition-rocks on the west, and is again succeeded in its turn by the second or new red sandstone in the vicinity of Kelso. This formation, however, occurring in small quantity, and so much out of the range of the following Flora, we shall not again refer to it particularly, but proceed, without farther remark, to give a very general description of the two others, noticing, as we go along, as many names of interest as possible, that, by glancing at the habitats assigned to the plants, in another part of these pages, we may at once be able to recognize these spots again, whether as belonging to the one or to the other class of rocks, and at the same time know what are the particular mineral substances which there predominate.

"Of those parishes within which habitats most frequently occur, we remark the following as belonging to the oldest of the two formations, the transition class, viz.: The northern division of the parish of Dunse, the parishes of Abbey St Bathan's, Buncle, Cockburnspath, Coldingham, Eyemouth, the greater part of Ayton, and part of Mordington. To the latter division, again, belongs the mouth of the Tweed, and neighbourhood of Berwick, the remaining parts of the parishes of Dunse, Ayton, and Mordington, nearly the whole of Foulden, and the whole of Hutton, Ladykirk, Chirnside, Whitsome, Swinton, Coldstream and Eccles.

"I shall begin with the first of these, and proceed nearly in the order now mentioned. The northern part of the parish of Dunse extends into the outskirts of the Lammermuirs. These hills, as already mentioned, belong to the transition series, the characterizing rocks of which are greywacke, and greywacke slate. It is difficult to ascertain whether or not the old red sandstone forms the connecting link between these rocks and the new red sandstone of the Merse; but it is probable, that with minute attention it may be observable †. In this part of our survey, the most striking and important feature of the scenery is Cockburn Law, a beautiful hill about 900 feet above the level of the sea, and equally interesting in an antiquarian, geological, and botanical point of view. The Whiteadder washes the base of this hill, on the northern bank of which, embowered in wood, lies the Retreat, a summer residence of much sweetness and beauty. The fundamental rocks here, as seen on the banks, and in the bed of the Whiteadder, are the greywacke and greywacke slate, but the greater part of the hill itself consists of transition granite, trap, and porphyry. The whole of Abbey St Bathan's, the adjacent parish towards the north, we believe to consist of the ordinary greywacke, and its accompanying slate, as also the parish of Buncle, towards the east, where copper has been wrought to a considerable extent, 'although, we believe, with very little profit to those engaged in the concern. In this part of our course the most interesting

* Greywacke has a basis of clay-slate, and in it imbedded portions of clayslate, grey quartz, and felspar. Generally, too, there is a good deal of mica in it, especially in the neighbourhood of that part of these hills now noticed. The slate is the same rock, only smaller grained, and having more clayslate.

The old red sandstone occurs in this manner farther towards the west at Longformacus, and in the neighbourhood of Greenlaw. At the former of these places, it forms the bed of the small river Dye.

botanical habitat is Buncle wood, a tract of ground about 100 acres in extent, and finely varied for the Botanist by smooth green turf, wild moor, and marsh.

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Proceeding still towards the east by Edineraw and Reston we arrive, after a mile or two, at the beautiful valley, extending, in a northerly direction, from Houndwood to Cockburnspath. The greater part of this valley is watered by the small river Eye; the whole bed of which, from its rise to its fall, appears to consist of greywacke, and its accompanying greywacke slate, with subordinate rocks of trap. Beds of peat, too, of considerable thickness, occur in the bottom of this hollow, and ex. tend for several miles beyond Houndwood and Renton Inns. The sides of the valley now noticed are lofty, and beautifully adorned, especially on its eastern side, by natural woods and extensive plantations. The rocks are all transition. Towards the northern end we come to the Pease or Peath's Burn, along whose steep banks, and underneath the magnificent arch of whose bridge we pass, till we arrive, in a short time, at its mouth, and the shores of the German Ocean.

"From this our course is naturally directed eastward along the coast, the whole line of which, for many miles, is very lofty, naked, and precipitous. Not having examined the whole of it with any thing like minute attention, it may be simply sufficient to ・ mention, that, throughout the greater part of its extent, from this point to the promontory of St Abb's, the rocks appear to be still greywacke and greywacke slate, the former being frequently broken in pyramids and insulated masses by the violence of the waves, and often exhibiting very curious and singular distortions in position and in stratification. The most interesting and striking object between the two points now al

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