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stone which reposes on the Laminermuir rocks, and is frequently a 

 coarse conglomerate, contains the scales of Holoptychius ; and at a 

 little distance in the direction of the dip, other and newer beds 

 are loaded with impressions of plants, probably marine. Red and 

 greenish-white sandstone and argillaceous red strata are followed 

 by impure concretionary limestone, termed corn-stones by our author, 

 and these pass upwards into sandstones and shale, enclosing plants 

 peculiar to the Carboniferous system. Occupying a great breadth 

 in the county of Berwick, and for the most part unproductive in 

 coal, some of these bands being of red colours, and containing gyp- 

 sum, were formerly mistaken for the new red sandstone. So long as a 

 too strict adherence to lithological characters, as decisive of the age of 

 formations, prevailed, doubts were thrown upon the age of the Ber- 

 wickshire coal-field ; for notwithstanding the memoir of Mr. Witham, 

 which distinctly showed that a part of this great red coal-field lay be- 

 neath the mountain limestone, and contained many species of true 

 carboniferous plants, the influence of the red and gypseous characters 

 of this deposit was all-powerful. The correct view, however, has 

 been maintained for some years by Professor Sedgwick and several 

 other geologists. 



Taking our earlier views chiefly from the English southern coal- 

 tracts, and not suflftciently attending to their far greater develop- 

 ment in the northern counties, we have been apt to force the larger 

 into too strict accordance with the smaller type. Geologists, there- 

 fore, who are well acquainted only with the carboniferous suc- 

 cession of Bristol and South Wales, must now learn, that the 

 lower limestone shale of these tracts (oftentimes indeed a sand- 

 stone) is the miniature representative of the enormously thick and 

 varied carbonaceous deposits of the South of Scotland. I may say 

 of Scotland, for it is quite evident, that some of the most productive 

 of the coal and iron-stone fields (many of them associated with much 

 red sandstone) in the centre of that country, occupy precisely the 

 same horizon ; their upper masses being interlaced with thin cal- 

 careous courses in which mountain limestone fossils prevail. I 

 shall revert to this subject in alluding to a recent work of Mr. Grif- 

 fith on the Geology of Ireland, Avhere the lower part of the carbo- 

 niferous system is enormously developed. 



In reference to Mr. Stevenson's effort to class the fossil beds of 

 the Old Red Sandstone near Dunse, I would observe, that we can 

 scarcely hope to separate this formation into all its true divisions, 

 by the aid of a very few scales of one or two species of fossil fishes 

 only. In Russia, for example, the very highest beds of the system 

 — beds absolutely in contact with overlying carboniferous strata, are 

 loaded with the Holoptychius nohilissimus; whilst in the same region, 

 strata, infinitely lower in the series, are charged with the Dendrodus 

 strigatus and other forms which are associated with the Holoptychius 

 nobilissimus in the very same stratum at Scat's Craig, near Elgin. 



Describing the dislocations around Dunse, Mr. Stevenson connects 

 them with trappean dykes, and sustains the original view of Mr. D. 

 Milne, that the Lammermuir chain has undergone two distinct up- 



