194 PROF. T. T. GROOM ON THE GEOLOGICAL [Feb. I9OO, 



the Silurian, so that in some places the May Hill Sandstone 

 (pp. 139, 142, 149, 152, & 1 60), in others the Woolhope Lime- 

 stone (PI. YIII), and in others the Wenlock Shale (p. 142) 

 are in contact with the Archaean. At West Malvern the 

 Cambrian appears to have been thrust on to the May Hill 

 Sandstone (p. 158) ; in Cowleigh Park, the Archaean on to the 

 same formation (p. 157); and near Martley the Archaean 

 appears to have been thrust horizontally over the basal 

 Cambrian, and these two again on to the Old Red Sandstone 

 (p. 163). In other parts of the Abberley Range portions of 

 the Silurian Series appear to have been thrust over other 

 portions of the same series (pp. 167-73). Thrusts of the 

 Archaean massif on to the Cambrian and Silurian rocks have 

 taken place also within the present limits of the massif itself. 5 



4. The overthrusts and upth rusts appear to have been to a certain 



extent independent of the first folding of the rocks, but are 

 closely connected with the process of overfolding which 

 took place later. (See p. 182.) 



5. The thrusts in most cases do not appear to have materially 



modified the nature of the rocks concerned in the process, 

 but in some places a secondary production of schists (mvlon- 

 ites) has probably taken place in the Archaean material in 

 the neighbourhood of the thrust-planes. (See p. 183.) 



6. In some cases a secondary folding appears to have affected the 



thrust-planes, in a way similar to that seen in the Scottish 

 Highlands. (See p. 163.) 



7. The intensity of folding diminished west of the old ranges, 



and in places a typical austonungszoneis seen. 2 



8. The movements undergone by the chain were complicated by 



the production of transverse faults, the blatter of German 

 writers. 



9. The West-of-England Chain appears to have been developed 



in several sections, the chief movements of the rocks having 

 progressed from north to south. (See p. 182.) 



10. The western fronts of these sections show some tendency 



towards convexity in the direction of movement, as in the 

 case of other more important ranges. (See p. 183.) 



11. The rocks affected by the great movements range from the 



Archaean to the older Coal Measures. (See pp. 165 et seqq.) 

 The Archaean mass itself in the Malverns shows deep and 

 narrow crushed infolds. 3 



12. The Upper Coal Measures and the * Permian ' rest relatively 



undisturbed upon the denuded rocks of the old chain. This 

 favours the view that the West-of-England Chain is a 



1 Pp. 146, 149.. 150, 152, & Quart. Journ. Geol. Soc. vol. lv (1899) pp. 142 

 et zeqq., pp. 150 et seqq. 



2 Quart. Jo; r\ Geol. Soc. vol. lv (1899) p. 156. 



s Ibid, pp. 1-12 et seqq., pp. 150 et seqq. ; see also pp. 146-47 & 152 of the 

 present paper. 



