196 Proceedings of the Royal Society of Edinburgh. 



of the basins of the Forth and Clyde. The additional information 

 contained in his paper comprised, in the first place, an account of the 

 older class of strata upon which the carboniferous group of rocks (in 

 which saurian remains had been found) were supposed, in an uncon- 

 formable position, to rest. Some of these were referred to a system 

 of beds, which geologists consider as of a newer transition class, in- 

 termediate to grauwacke schist and coal strata. Thus, it was found 

 that a peculiar hard and gray sandstone, containing mica, and occasion- 

 ally alternated with siliceous schist, — which in Slietland succeeds to 

 clay-slate ; %vhich, near Loch Ness, succeeds to a transition granite ; 

 and, on the north of the Tay, to grauwacke schist, — was thrown up on 

 the south of the Forth, near North Berwick, in the form of immense 

 severed beds or fragments, shewing that this transition-rock (an im- 

 portant one in the series of Scottish strata) is to be regarded as in 

 some places fundamental to the coal measures of the district. This 

 older grey sandstone is also alternated, either with aluminous strata 

 of the same general character, or with a hard sandstone of a reddish 

 colour. 



The carboniferous deposits inclosing saurian and other remains 

 which rest in an unconformable position upon these strata, were for- 

 merly shewn to contain inferior beds of sandstone, shale, and fresh- 

 water limestone, together with very thin seams of coal and ironstone; 

 and to be succeeded, first, by a limestone containing marine shells, 

 encrinites, corallines, &c., and afterwards by extensive coal measures 

 which formed the upper beds of the series. This is shewn in the fol- 

 lowing general section of the strata connected with the limestone of 

 Burdiehouse. 



In arguing from these appearances, the author considered that, at 

 the commencement of the Carboniferous epoch, the coal beds of the 

 Forth and Clyde did not, agreeably to received theories, indicate an 

 Archipelago of islets, like those of the Pacific, little elevated above 

 the level of the sea, but, on the contrary, an unliroken expanse, 

 bounded on the north by the elevated ranges of the Grampians, and 

 on the south by the high ridge of grauwacke schist which runs from 

 St Abb's Head to the Mull of Galloway ; and that while the higher 

 lands might have encouraged the growth of coniferae, the ferns, 

 equiseta, and other monocotyledonous plants of our coal-fields, 

 flourished amidst marshes, or on the borders of fresh-water lakes, 

 tenanted by entomostraca, conchifera, and fish, and to which resorted 

 various saurian animals. This land, as had been previously remark- 

 ed, appears to have undergone a depression, probably of a gradual 

 nature, by which it became liable to the inroads of the sea. Eventu- 

 ally, however, (as the extensive coal strata lying above the marine 

 limestone sufficiently indicate), the land became once more elevated 

 above the ocean, and again aflPorded a soil to the Flora of tropical 

 climates. 



The author next remarked, that he had found a fresh-water de- 

 posit, like that of Burdiehouse and Calder, to extend to Fifeshire, 

 where it existed as a thinner bed ; and that, in addition to the co- 

 prolites and fish discovered more than a year ago by Lord Greenock 

 and Mr Trevelyan in the iron-stone nodules of Wardie, Mr Robison, 

 (general Secretary of the Royal Society, had procured saurian remains 



