Vol. 56.] INLIER AT OLD RADNOR. 515 



(b) Lithological Comparison with other Groups. 



The Old Eadnor Series is distinctly unlike both the Ordovician 

 and the Cambrian of the Western Midland area. If Ordovician rocks 

 exist in the Eadnor district, they must be of the Caradoc type, 

 for the Stiper Stones Series lies far to the west at Builth. But the 

 Caradoc strata of the country east of Church Stretton are mainly 

 quartzose sandstones and soft shales. The Cambrian of Shrop- 

 shire is made up of quartzite and green arenaceous grits, overlain 

 by the Shineton Shales. These shales occur in their typical facies 

 at Pedwardine, only 9 miles from Old Eadnor; and it is fair to 

 assume that, if the Lower Cambrian strata were also continued along 

 the line of strike, they would be similar to the Salopian types. This 

 supposition is rendered almost a certainty by the fact that Cambrian 

 rocks, both Upper and Lower, do appear as far south as the Malvern 

 Hills, and are so similar to the Shropshire subdivisions as to be 

 easily identified by their lithology alone. No one familiar with 

 the Cambrian and Ordovician rocks east of Church Stretton could 

 fail to perceive their great dissimilarity to the felspathic grits and 

 hard slaty beds of Old Eadnor Hill. 



The lithological resemblances between the Old Eadnor Series and 

 the typical Longmyndian are very well marked. In a previous 

 paper, 1 descriptions by Prof. Bonney and myself have been given of 

 the ordinary Longmynd types. They indicate derivation from land 

 composed of gneisses, granites, and rhyolites. A few extracts from 

 these descriptions are here appended : — 



' Composed of bits of quartz, purple rhyolite, mica-schist, and felspar. Largely- 

 derived from granitoid rocks . . . .Composed of quartz, felspar, and a small 

 proportion of volcanic fragments. . . .Bits of quartz and felspar, with mica and a 

 small proportion of felsite.' 



The abundance of felspathic material in these slides is charac- 

 teristic of the typical Longmyndian, and the same feature is well- 

 marked in the Old Eadnor Grits. The angularity of the quartz, 

 felspar, and felsite is also common to the grits of both areas. The 

 close lithological resemblances between the two rock-groups, com- 

 bined with the evidence of geological position and unconformable 

 relation, would seem to place their identity beyond reasonable doubt. 



4. The Alleged Metamorphism of the Eocks of the 

 Old Eadnor Area. 



Both the Old Eadnor Series and the Woolhope Limestone are 

 said to have been metamorphosed. Let us take the two cases in 

 order. 



O) The Old Eadnor Series. 



I have already stated that these rocks do not display material 

 alteration. The felspar, it is true, often contains microliths of mica r 

 but this feature is common in the old gneisses and granites, and 

 there is no evidence that the alteration took place after the con- 

 version of the crystalline material into sediments. Infiltration is 

 1 Quart. Journ. Geol. Soc. vol. xlii (1887) p. 482. 



