450 Geological Society. 



detached portions, and generally accompanied by indications of 

 disturbance, obviously proceeding from the primary masses on 

 which they at present repose. It would exceed the limits to which 

 I am here confined, to detail the results of which these memoirs 

 give an account : the general inferences are, — 1. The identity with 

 the secondary rocks of England, of the strata in the Western-Islands, 

 and throughout a large portion both of the east and west coasts of 

 Scotland, is established on the evidence of fossils. — 2. A formation 

 of red sandstone has been observed, on the shores of the Pentland 

 Firth, which appears to occupy a place between the coal-measures 



and the new red conglomerates 3. A great deposit of sandstone, 



with subordinate beds of dark bituminous limestone, occupying, ap- 

 parently, the place of the coal-formation, has been designated, — but 

 not yet perfectly identified with any formation hitherto described. 

 The great thickness of this deposit and the ancient character of 

 the rocks subordinate to it, prevent its reference to the German 

 copper-slate : but the bituminous beds in Caithness contain impres- 

 sions offish, including two new genera, with other fossils, all resem- 

 bling those of the inhabitants of fresh water. — ■i. The principal rela- 

 tions have been determined, of the conglomerates and sandstones 

 which occur upon the north-west coasts, and the north-east of the 

 Highlands, and range along the southern flank of the Grampian 

 chain : and this great deposit is shown to be identical with the old 

 red sandstone of England. 



The disturbance of some of the newer strata in Caithness, is refer- 

 red by the authors of these papers to the elevation of the granite be- 

 neath ; the amount of disturbance being in all cases nearly propor- 

 tioned to the proximity of that rock : and it is rendered probable 

 that the crystalline compound was upheaved, not in a fluid state, but 

 after its consolidation ; since, although veins are numerous in other 

 cases of contact of granite with incumbent rocks, neither veins nor 

 detached portions of the granite are in these instances to be met with 

 in the shattered secondary strata which are placed upon it. There 

 are few points more interesting to theory, than the general existence 

 of such derangements on the confines of the primary and crystal- 

 lized masses and of the stratified rocks : and this, without any other 

 evidence, might have led to a suspicion that the former were them- 

 selves the instruments by which these dislocations were effected. 



The existence in the N.W. of Scotland, of portions of strata pro- 

 bably deposited in freshwater, is another very interesting fact, for 

 which we are indebted to Professor Sedgwick and Mr. Murchison : 

 and it is particularly remarkable that the masses of limestone of 

 this description discovered by these observers in the Isle of Skye, 

 contain several of the same fossils (two species of cyclas, a palu- 

 dina, and an ostrea) which occur also in the Weald-clay of our 

 south-eastern counties*. 



It is my office here, to mention what has been done by our con- 

 tributors, 



* It deserves to be mentioned, that a species of cyclas very like the 

 medius of the weald-clay (Sowerby, Min. Conch, tab. 527. fig- -■) and of 



Skve, 



