ON THE STOCKDALE SHALES. 



687 



Pull BecJc, 



The extensive bay of Pull Wyke, on the west side of Windermere 

 and close to the head of the lake, is due to the soft rock of the 

 Stockdale Shales, which are masked to the westward by the exist- 

 ence of an alluvial flat, through which the stream called Pull Beck 

 runs. Crossing over this stream by the bridge over which the 

 Coniston road runs, we may follow the latter road past the great 

 Brathay Plag-quarries to a cart-track which turns to the right 

 through a gate immediately beyond the quarries. If we follow this 

 cart-track we are presently brought down to the stream near some 

 cottages. The Skelgill Beds are exposed in numerous more or less 

 isolated outcrops in the bed and banks of the stream and in the lane 

 north of the cottages ; but they are so cut up by numerous minor 

 dip-faults as to assume the character of a fault-breccia on a large 

 scale, and any attempt to make out a succession is futile. The 

 Atrypa-flexuosa limestone is seen in the lane north of the cottages, 

 and has the same character as at Skelgill ; but no fossils were found 

 here. The Dimorjpliograptus-confertus Beds occur in the stream by 

 the bridge at the cottages, and contain numerous well-preserved 

 specimens of Monograptus revolutus, Murch. The Middle Skelgill 

 Beds are seen in many places, and the fossils of most of the zones 

 can be collected in an admirable state of preservation, as the beds 

 in this faulted tract have escaped to a great extent the effects of 

 cleavage. In the wood west of the cottages a small exposure of 

 the aloniensis-zone occurred and yielded an excellent specimen of 

 Proetus hracliypygus, n. sp. Beyond the wood the stream runs 

 through a few fields to a small spinney called Redding Coppice, and 

 there receives a tributary from the west, whilst the main stream 

 flows from the south-west. In the main stream, just above the 

 point of junction with the tributary, the black bands of the crispus- 

 zone occur, and the fossils at this point are in a better state of 

 preservation than in any other exposure of this zone which we have 

 met with. They include : — 



Monograptus crispus, Lapw. 



exiguus, Lapw. 



pandus, Lapw. 



■ discus, Tornq. 



Hisingeri, Carr. 



Cyrtograptus ? spiralis, Gein. 



Eetiolites Geinitzianus, Barr. 



perlatus, Nick., var. 



Petalograptus palmeus, Barr. 



, var. tenuis. 



Peltocaris. 



Higher Browgill Beds occur further up the stream. Just west of 

 this point a great dip-fault shifts the beds five sixths of a mile to 

 the south, and the pale shales of the Browgill Beds are seen in a 

 beck coming down the hill from the west, just south of Sunny Brow. 

 Here they are of no great interest, and although several exposures 

 of Browgill Beds and occasional patches of the Skelgill Beds are 

 seen between here and the Coniston Valley, no section of particular 

 interest is found till Coniston Waterhead is reached. There are 

 some exposures of Skelgill Beds in a stream near the Waterhead 

 Hotel ; but the best sections occur further west. 



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