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Malvern representative of the Lingula flags, it follows that a very long interval 

 must have elapsed between the respective epochs at which the two formations 

 ■were accumulated ; and as the Hollybush sandstone rests transgressively on 

 the gneissic rocks, while on the contrary there is perfect conformity between 

 the Lingula flags and the Cambrian rocks, we infer that whatever sediments 

 were deposited upon the gneissic rocks during this long interval, over the 

 area not now covered by newer formations, must have been stripped off 

 again by denudation before the sandstone was deposited. Hence we may 

 conclude that the Cambrian rocks are absent from beneath the Hollybush 

 Bandstone, and that the crystalline rocks belong to a yet eirlier epoch. 



There are, however, reasons for supposing that at some former period 

 the gneissic rocks were covered by other sediments, which were again 

 removed from off them before the era of the Lingula Flags, except, perhaps, 

 certain rocks on the eastern slopes of the Herefordshire Beacon, which are less 

 highly altered than the crystalline rocks of the ridge, and are clearly of a later 

 date, and which, it is quite possible, may be a remnant of tliese missing 

 strata. Unlike the older gneissic rocks, they appear to owe theit altered 

 condition to local causes, viz., to the intercalation of beds of lava and to trap 

 dykes ; and I formerly regarded them as part of the Lingula Flag series, but of 

 this there is no certain evidence, and it is equally possible that they may be 

 older ; but as the relative position of these rocks to the Hollybush sandstone is 

 not known, it is impossible to say whether they may belong to the Cambrian 

 system or to some more ancient one. 



We have rocks supposed to be Cambrian on the South at May HUl ; ve 

 have them on the North-East at Charnwood Forest, resting directly on rocks 

 precisely similar to those of the Malverns ; we have them on the North-West 

 at Haughmond Hill and the Longmynds ; and we know that subsidence was 

 going on at the epoch of the Hollybush Sandstone, and had probably com- 

 menced long anterior to that date ; and from this and other evidence I infer 

 that at the commencement of the Cambrian period there was in central 

 England a large area of land which culminated in a mountain ridge, which is 

 now the Malverns, and that as this tract subsided, fresh deposits succes- 

 sively crept forward towards the ridge, and progressively decreasing the area. 

 But I do not think that there is any evidence that the ridge became sufS- 

 ciently depressed for deposition to take place upon its flanks, untU the 

 period of the Lingula Flags. 



This paper gave rise to an interesting discussion. Professor Morris took 

 the same view with Dr. HoU, and considered that there was no evidence of 

 igneous action observable in the Malvern chain. They were in reality a gneissic 

 range of metamorphic structure synchronising with the Laurentian rocks of 

 Canada, not of truly igneous origiu, though penetrated at various parts by 

 irruptive veins of syenite and dykes of trap, and went into a long train oS 

 argument on the subject, illustrating his remarks with diagrams. 



