Vol. 56.] STRUCTURE OF THE MALVERN AND ABBERLKY HILLS. 183 



Malvern Kange ; the latter, in their turn, appear to have been 

 produced somewhat earlier than the southernmost portion, the only 

 remnant of which is seen in Chase End Hill, for the schists of the 

 latter appear to have overridden the Cambrian strata, the folds of 

 which are parallel to the Archaean axis at the southern end of 

 Iiaggedstone Hill. The West-of-England chain appears, therefore. 

 to have been successively evolved in sections from north to south. 



It may be noted that the two northern sections show a tendency 

 towards convexity of the western or front margin, a circumstance 

 frequently observed on a much larger scale in the case of great 

 mountain-ranges. If the southern extremity of the range was 

 originally continuous with the May Hill elevation, in the general 

 direction of which it points, a similar tendency may have been ex- 

 hibited here also, for the axis in that case running south-westward 

 must gradually turn and unite with that of the southern part of the 

 May Hill anticline. The Y-shaped disposition of the May Hill 

 mass, pointed out by Phillips, 1 suggests, indeed, a former connexion 

 between the folds of the two districts. It may be noted that a 

 secondary production of schists from the old Archaean material 

 appears to have taken place in the case of each of the three sections 

 of the chain. 3 



The movement in each section of the chain probably took place 

 in more than one stage. Thus, in the main mass of the Malvern 

 Kange the elevation appears to have commenced with gentle folding, 

 and to have culminated in a powerful upthrust or overthrust/, 

 accompanied by overfolding (p. 182). Moreover, the thrust-planes 

 themselves appear to have undergone secondary folding. 3 At Walls- 

 grove Hill, in the Abberley Pange, the disposition of the passage- 

 beds and their relation to the Aymestry Limestone suggest that the 

 overfolding culminated in overthrust (p. 167). At Hartley the over- 

 thrust rocks appear to have undergone subsequent folding and 

 faulting (p. 163). 



XIX. The Relation of the Hatfield Breccia to the 

 Underlying Formations. 



It has been long recognized that the Haffield Breccia in the 

 Malvern and Abberley districts rests with striking unconformity 

 upon the Lower Palaeozoic and Archaean rocks. 4 At certain points 

 it is separated from these older rocks by thin strips of Coal Measures 

 (p. 176), w r hich must be inclined at an angle differing but little 

 from that of the Breccia itself. The presence of Coal Measures 

 beneath the Breccia at some points, and their absence at others, can 

 be explained only by one or other of two hypotheses. The Breccia 



1 Mem. Geol. Surv. vol. ii (1848) pt, i. p. 181. 



2 Quart. Journ. Geol. Soc. vol. lv (1899) pp. 153 & 157; Geol. Mag. 1898, 

 p. 562 ; and pp. 141, 142, 163 & pi. viii of the present paper. 



3 Quart. Journ. Geol. Soc. vol. lv (1899) pp. 154 & 155 ; see also p. 163 of 

 the present paper. 



4 Mem. Geol. Surv. vol. ii (1848) pt. i, pp. 112, 113, 1 ' T "3, 161, etc. 



