214 MISS G. L. ELLES AND 1VIISS I. L. SLATER ON THE [May I906, 



The succession of these highest beds is more clearly seen 300 yards 

 west of the stream below the track to Downton-Castle Bridge. 

 Here the olive shales are well exposed, with the characteristic gritty 

 * Fragment-Bed' at their upper limit. We were uuable to detect 

 this in the stream-section, but it is here immediately overlain by 

 the same massive red sandstones as those which form the upper 

 waterfall of the stream. 



The chief points wherein these beds in the neighbourhood of 

 Downton Castle differ from those at Ludlow, are the thinning of the 

 Platijschisma-Bed to a Bone-Bed and the thickening of the olive 

 shales (Fc&P e). 



(v) Mocktree. 



Owing to the faulting in the northern part of the area, a satis- 

 factory line of section is difficult to obtain, but a fairly typical one 

 can be made out along the Leintwardine-Ludlow road. 



The Aymestry Limestones (A) are still being worked in a series of 

 quarries along that part of the road which runs through Wassell 

 Wood ; but in the large quarry 130 yards west of the Briery a small 

 fault running from north-west to south-east drops the Mocktree 

 Shales (B) down against the limestones, and the fault is well seen in 

 the face of the quarry. The lowest limit of the Mocktree Shales is 

 also visible and is somewhat peculiar, suggesting that at this horizon 

 erosion of the limestones was being carried on during their deposi- 

 tion. 1 This section has been recently figured in the Proceedings 

 of the Geologists' Association, vol. xviii (1904) pi. xlii, fig. 1. 



The Mocktree Shales, crowded with Day la navicula, are exposed 

 more or less continuously for 600 yards along the road, but then 

 the succession is interrupted by a west-north-west fault, and con- 

 sequently the same beds are still seen for another quarter of a mile 

 along the road. They are more extensively developed here than 

 anywhere else in the district, attaining a maximum thickness of 

 150 feet. On each side of Fiddler's Elbow the basal beds of the 

 Lower Whitcliffe Flags (C) are seen, and south-east of Hillpike 

 Farm Upper Whitcliffe Flags (D) are well displayed in an old quarry 

 on the south side of the road, and in the banks of the road itself. 

 On the north side of the road near Lodge Lane, the highest members 

 of the Downton-Castle Sandstones (E) have been quarried in a 

 small plantation. 



(vi) Sections near Onibury. 



(a) Craven-Arms Road. 



Another section showing the relationships of the highest Silurian 

 rocks may be seen along the road from Craven Arms to Onibury, 

 6 miles north-west of Ludlow. The Aymestry Limestones (A) are 

 exposed a little more than a mile north-west of Onibury, on the north 

 side of the road, dipping 15° eastward; and from this point to the 

 milestone there is a nearly-continuous exposure in the road and in 

 the river-bank, along which the characteristic honeycomb-weathering 

 is most clearly seen. The succeeding Mocktree Shales (B) are well 



1 Lightbody, Quart. Journ. Geol. Soc. vol. xix (1863) p. 368. 



