Vol. 55.] GEOLOGICAL STEXJCTTJRE OF THE SOUTHERN MAL VEENS. 137 



the more thinly-bedded flaggy and shaly series seen in the sections 

 hitherto described. 



Summarizing the relations of the schists and sandstones seen in 

 the large quarry, it may be stated that the plane of junction is a 

 fault, showing a close but variable relation, on the one hand, to the 

 strike of the schists, and on the other to that of the sandstone. 

 Prof. Lapworth informs me that the schists are of the nature of 

 mylonites. 



The dips of the sandstone beyond the limits of the quarry are 

 shown by arrows in the sketch-map (fig. 2, p. 134). 



To the south the Hollybush Sandstone appears to be entirely cut 

 out by faulting, and the Black Shales brought into direct contact 

 with the gneissic series. Almost everywhere else along the line of 

 fault the sandstone itself seems to be in direct contact with the 

 gneissic series, but on the slope due west of the summit (see fig. 1, 

 p. 132) debris of a quartzite and conglomerate may be found. In 

 these I have obtained numerous specimens of Kutorgina cingulata 

 and other fossils. This fossiliferous rock is not now exposed in 

 place, but Symonds ^ states that it was formerly quarried, and could 

 be seen to dip at a high angle beneath the Hollybush Sandstone. 

 At a point not far from the summit, and about 35 yards south of 

 the outcrop of the diorite in the gneissic series, is a shattered 

 quartzose rock, forming a tump near the end of a line of bushes 

 and trees running up the slope. I have little doubt that this is the 

 Hollybush Quartzite modified in the vicinity of the fault, but no 

 fossils were obtained from it. 



The general relations which have been indicated between the 

 gneissic series and the flanking Cambrian deposits are, I think, 

 incompatible with the idea, suggested by Holl, of an unconformity 

 combined with rapid overlap, and can be adequately explained only 

 by a fault. This is in harmony with the opinion expressed by 

 Dr. Callaway," though no evidence in favour of this view was adduced 

 by him. 



The practically straight course of both the northern and southern 

 parts of this fault, as they cross the contour-lines, suggests that the 

 fault is on the whole nearly vertical, although, as seen in the large 

 quarry to the south, it has by no means everywhere a plane 

 surface. 



The relations of the sandstones forming the north-western corner 

 of Baggedstone Hill, to those constituting the narrow strip on the 

 south-western flank of the hill, are not clear. The dip in the former 

 locality, as already indicated, is at a moderate angle towards the 

 west-north-west, while in the latter case it is usually south-westerly 

 or west- south-westerly, at a higher angle, and is occasionally 

 reversed. Judging from the occurrence of quartzite at several 

 points along a line running down the slope (fig. 1, p. 132) and from 



1 ' Old Stones,' 2ad e:l. (1881) p. 24. 



2 Geol. Mag. 1879, p. 219. 



