94 PKOCEEDINOS OF THE GEOLOGICAL SOCIETY. 



and the identity of these altered rocks with the Upper Cambrian 

 beds on the west of the southern extremity of the range is, I think, 

 more than probable. 



Of the trap-rocks which have been intruded into this area, four 

 form irregular masses of some size, one of which is situated imme- 

 diately to the north of the cave, and another to the south and south- 

 west of it. A third occurs a quarter of a mile to the north-east of 

 the cave, and a fourth about the same distance to the south-east 

 of it, on the brow of the hills overlooking a farmhouse. The re- 

 maining outbursts form linear dykes, of which there are ten or more 

 traversing the area in different directions. These trap-rocks differ 

 in their physical appearance from the other trap-rocks of earlier 

 date in their more confusedly crystalline structure, and, the majority 

 of them, in their larger proportion of augite. In a few the felspar 

 predominates. The felspar is of a brown or dull-greenish colour, 

 and sometimes exhibits iridescent reflexions. In chemical constitu- 

 tion these traps resemble those previously described, and consist, 

 according to Mr. Timins, of aluminous augite and labradorite, or an 

 allied felspar. Their probable age will be alluded to hereafter. 



TV. UrpEK SiLUEiAisr Rocks : May Hill or Upper LlandovePvY 



Rocks. 



All the remaining members of the Lower Silurian series are absent 

 from the district, and the May HilL rocks which succeed have been 

 laid down unconformably on the denuded surfaces of the Black Shales 

 and HoUybush Sandstones. These Llandovery beds, emerging from 

 beneath the Permian conglomerate of Bromesberrow Park at Hayes 

 Copse, form a semicircular escarpment which, passing west of 

 Rowick and Bransill Castle, closes in upon the hills near the northern 

 extremity of Midsummer Hill. Some of the flaggy light-brown 

 basement-beds, however, cap the higher ground on either side of the 

 Ledbury and Tewkesbury turnpike-road, as seen above the lava-bed 

 at Rowick, and to the north and east of it. More massive brown, 

 greenish, and purple beds overlie these, and are seen at Howler's 

 Heath and below the Obelisk at Eastnor ; but the beds which flank 

 either side of Swinyards Hill are still higher in the series, and at the 

 " Silurian Pass," at its northern extremity, the upper part of the 

 Llandovery, with its alternating bands of arenaceous limestone, rests 

 directly on the crystalline rocks of the hills. 



On the west of the Herefordshire Beacon the May Hill Sandstone 

 is cut out altogether by a fault, but some of the lower purple beds 

 occur high up on the hills in the rear of Mr. Johnson's house at the 

 Wind's Point, being faulted into that position, and having a north- 

 easterly dip. Round the point, on the western slope of the hill, 

 towards Brand Lodge, and thence on towards the Wj^ch, higher beds 

 only rest on the metamorphic rocks, although seen at a lower level. 

 None of the lower purple and conglomeratic beds of the May Hill 

 rocks again occur until we arrive nearly at West Malvern, where 

 they reappear between the flaggy beds and shales which form the 

 upper half of the series and the crystalline rocks of the hills, and, 



