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A HISTORY OF HEREFORDSHIRE and Silurian deposits overlapped the metamorphic series, which he considered was composed of metamorphosed sedimentary and igneous rocks of Pre- Cambrian age.' The Rev. W- S. Symonds, who knew Siluria second only perhaps to the ' Silurian Chief ' himself, also believed that the Malvern rocks were altered sediments ; ^° and Mr. Rutley has expressed the opinion that they were formed from metamorphosed tuffs, grits, and sandstones, as well as from volcanic and other igneous rocks." Dr. Callaway's views, how- ever, namely, those outlined above, have been endorsed by Professor Groom in his exhaustive stratigraphical papers on the Malvern Hills," and, as we have said, are the most generally accepted. On the other side of the Herefordshire syncline, on the borders of this county and Radnorshire, are five prominent hills. Two, Old Radnor and Yat Hills, are on one axis trending north-east and south-west ; and three, Stanner, Worsel Wood, and Hanter Hills, on another parallel to the first. A portion only of Stanner Hill is in Herefordshire. The rocks com- posing it are gabbros, dolerites, felsites, and granitoid rocks, and their age is still under discussion. Cambrian System Cambrian Beds occur in Herefordshire on both sides of the syncline — in the South Malvern district, and at Pedwardine, near Brampton Bryan. Throughout the Cambrian Period Herefordshire was beneath the sea. The coast-line of the mainland was situated to the north-west. In Wales the thickness of this system has been estimated at i i,ooo ft. ; but to the east it rapidly decreases, being in Warwickshire about 3,000 ft. Towards the close of the Cambrian Period movements of the sea-floor took place and a land-surface, probably an island, was formed in what is now called the Midland counties. In the Midland counties and the Welsh borders the deposit made in the early part of the period was sand, and in the later — until the uplift of the sea-floor occurred — dark-coloured shale. So the Cambrian as developed in the Midlands can be divided into a Lower or Arenaceous Division and an Upper or Shaly. In those parts of Herefordshire where the Cambrian rocks occur at the surface a similar dual division can be recognized. In the South Malverns the Arenaceous Division is represented by the HoUybush Sandstone with the Malvern Quartzite at its base, and the Shaly Division by the ' Malvern Shales ' ; while intrusive in both are numerous sills and dykes of several kinds of igneous rocks. The HoUybush Sandstone and Malvern Quartzite, being the older beds, occur nearest the hills, while the shales are a little removed therefrom. Owing, however, to the causes which elevated the Malvern Hills these arenaceous and shaly deposits are very much faulted, and their geographical distribution and mutual relations difficult to determine. Professor Groom, " Quart Jout-n. Geol. Soc. xxi (1865), pp. 89, 92, 99, etc. ; see also Trans. Woolhpe Nat. F. C. 1866, np 270-4 ; Tram. Malvern Nat. F. C. pt. 3 (1853-70), p. 51. 10 < The Flora of Herefordshire,' Tram. Woolhope Nat. F. C. 1866 (1867), pp. 1-25. " Quart. Journ. Geol. Soc. xliii (1887), p. 508. " Ibid. Iv (1899), pp. 129-68 ; ibid. Ivi (1900), pp. 138-97- 6