Metamorphic Rocks of the Malvern Hills. 71 



The author referred especially to the paper by the late Dr. Holl, 

 whose work he, in the main, confirmed. Dr. Holl's object was to 

 demonstrate that the rocks which had hitherto been treated as 

 syenite, and supposed to form the axis of the hills, were in reality 

 of metamorphic origin, and belonged to the Pre-Cambrian. Mr. 

 Rutley restricted his observations to the old ridge of gneissic syenite, 

 granite, &c, which constitutes the main portion of the range, and, 

 reversing the order of his predecessor, commenced at the north end 

 of the chain. 



He considers that the beds of crystalline rock, mostly of a gneissic 

 character, in the old ridge have been disposed in a synclinal flexure, 

 which stretched from the north end of the chain to the middle of 

 Swinyard's Hill, where they receive an anticlinal flexure, and are 

 faulted out of sight. The length of this synclinal fold, would be 

 over 5^ miles. The lithological evidence is in favour of the rocks 

 forming the north part of Swinyard's Hill being a repetition of 

 those on the Worcestershire Beacon. We might expect to find the 

 older beds having the coarsest granulation, and being even devoid 

 of foliation, and this is what occurs on the Malverns, where the 

 northern hills are made up of the coarsest rocks, with finer schistose 

 beds towards the south ; the exception is at Swinyard's Hill ; hence 

 there are two groups of coarsely crystalline rocks at either ex- 

 tremity of the presumed synclinal. The contrast between these and 

 the fine-grained rocks of the other portions of the range has already 

 attracted attention. The most northern of the coarse-grained 

 masses is cut off towards the south by a fault near the Wych, while 

 the other lies between a fault on the north side of the Herefordshire 

 Beacon and the before-mentioned fault on Swinyard's Hill. 



The metamorphic rocks of the Malverns seem, therefore, to be 

 divisible into three series extending from the North Hill to Key's 

 End. A Lower, of coarsely crystalline gneissic rocks, granite, 

 syenite, &c, a Middle, of gneissic, granitic and syenitic rocks of 

 medium and fine texture, and an Upper, of mica-schist, finely crys- 

 talline gneiss, &c. A diagrammatic section shows the distribution 

 of these ; the northern block, extending as far as the Wych, consists 

 of the Lower and the lower part of the Middle ; the central block, 

 from the Wych to the fault in Swinyard's Hill, consists chiefly of 

 the Lower and upper Middle, but with a portion of the Lower at 

 the south end. The southern block, south of the fault on Swinyard's 

 Hill, consists wholly of the Upper series. 



How far the foliation of these rocks and their main divisional 

 planes represent original stratification must, the author thought, 

 remain an open question. It has been held that the strike of foliation 

 lies parallel to the axis of elevation ; but this is far from being the 

 case in the Malverns. Still a once uniform strike may have been 

 dislocated by repeated faulting. 



The author further discussed the general question of how far 

 foliation may or may not coincide with planes of sedimentation. 

 He admitted that the absolute conversion of one rock into another 

 by a process of shearing has been shown to occur, but doubted 

 its application in this case. Although he is inclined to believe 



