482 



MK. P. EUTLET 01ST THE EOCKS 



southern member of the Malvern range, and after a more detailed 

 description of it Dr. Holl carries the reader gradually northward. 



Without following his description further at present, I will at 

 once venture to expound the view to which my own examination of 

 the range, coupled with a careful perusal of Dr. Holl's paper, has led 

 me — a view which begins at the other end of the chain, and which, 

 if true, may result in a better understanding of its structure. 



In the first place, the beds of crystalline rocks, mostly of a gneissic 

 character, which form the axis of the Malvern range have, I believe, 

 been disposed in a synclinal flexure, which stretched from the north 

 of the range as far as the middle of the ridge which forms Swin- 

 yard's Hill, where there is, I think, evidence to show that they 

 experience a sharp anticlinal flexure and are then faulted down- 

 wards, to reappear no more in this country. The synclinal fold just 

 mentioned, which is over five miles and a half in length, is probably 

 more or less irregular through subordinate crumpling of the beds, 

 and, in common with the rest of the range, is traversed obliquely by 

 a number of approximately 1SLW. and S.E. or N.E. and S.W. faults, 

 as already indicated by Dr. Holl. 



Inferences regarding the upthrow or downthrow of the masses 

 lying between these faults may, perhaps, be most safely arrived at 

 from the corresponding displacements of the Silurian strata which 

 occur on the western flank of the range, and although from a little 

 north of Malvern Wells to the extreme north of the chain there 

 appear to be successive downthrows to the north, yet south of 

 Malvern Wells the throws vary. 



From lithological evidence generally, it seems that the rocks 

 forming the northern portion of Swinyard's Hill are a repetition of 

 those which constitute the Worcestershire Beacon, and the assumed 

 relationship of the beds is indicated in the diagrammatic section 

 appended to this paper (facing p. 488) *. 



We may infer that probably, but not necessarily, the oldest and 

 once most deeply-seated beds of gneiss would be those which would 

 have undergone the greatest alteration, that traces of bedding in 

 them would be rare or very obscure and irregular, and that in 

 crystalline structure they would approximate more closely to plutonic 

 rocks than the higher beds of the series. In other words, we should 

 expect to find the older beds occurring in the condition of coarsely 

 crystalline gneiss, or even of crystalline rocks devoid of foliation, 

 and the younger of finer texture and approximating to schists. 



In the Malvern range we find the most coarsely crystalline rocks 

 in the northern, and the fine-grained rocks and schists mostly in the 

 southern hills. Hence it may, 1 think, be inferred that the rocks 



* On referring to Phillips's Memoir, the following statement concerning what 

 he termed " mottled syenite " will be found : — " As already observed, it is in the 

 northern parts of the Malvern range, and especially north of the Worcestershire 

 Beacon, that this beautiful rock appears most abundantly. It is, however, not 

 entirely absent from any of the hills, at least in small masses. On the crest of 

 Swinyard's Hill it may be found amidst the great variety of compounds which 

 that narrow and interesting ridge presents." (Mem. Geo!. Surv. vol. ii. pt. 1, 

 p. 41.) 



