274 MESSRS. A. HARKER AND J. E. MAKE ON 



Shales, and the higher portions of tha Upper Limestone. The lower 

 part of the latter at the Spa Well consists of 15 feet of nodular 

 limestone, and banded limestones in calcareous shales, all somewhat 

 hardened, but not greatly metamorphosed. It passes down into 

 the breccia, which is very calcareous in its upper six feet, 

 and crowded with small fragments of rhy elite, whilst the lower 

 thirty feet consists of calcareous shales and grits with few rhyolite- 

 fragments. The lower part of the breccia contains casts of Lhul- 

 strcemia and fragments of large trilobites in places, whilst a thin 

 grit associated with it yields numerous Tentaculites. After a short 

 interval, 10 feet of flaky rhyolitic ash is seen dipping down stream 

 at a low angle, and then a break of many yards is occupied by the 

 red conglomerate. At the top of the Hotel Plantation is a claret- 

 colonred felsite with quartz crystals aud tolerably large porphyritic 

 felspars. Although this is in the position of the rhyolite between 

 the two limestones in Stockdale and elsewhere, we have satisfied 

 ourselves that it is intrusive. There is considerable disturbance 

 at the junction between it and the underlying limestone, which is 

 about sixty feet thick, and consists of calcareous bands and nodules 

 interstratified Avith more shaly beds. 



The top of the Rhyolitic Group is a nodular rhyolite, and, 

 after another interval occupied by Carbouiferous conglomerate, 

 we meet with an alternation of more or less altered rhyolitic 

 ashes, breccias, and lava flows, and one thin andesite, which 

 extend up Blea Beck to the W. side of the high road, where 

 they are faulted against the vesicular andesites and banded ashes 

 of the south side of Tewsett Pike. 



Hitherto we have merely considered the general succession of 

 the beds without reference to their changes of strike and the faults 

 by which they are aff'ected, and it remains to say a few words 

 concerning these. 



The normal E.X.E.-W.S.W. strike of the Silurian strata and of 

 the Coniston Limestone Group is slightly changed in the vicinity 

 of the granite, curving round its southern margin. The Ehyolitic 

 Group has its strike more strongly deflected, for the rocks turn 

 somewhat sharply towards the S.E. on the western side of the 

 granite, and appear to curve round with a mean X.E.-S.W. strike 

 on the eastern side. The andesites dip at first in a southerly 

 direction on the S.AV. margin of the granite, though farther north 

 they appear to turn over, and maintain a general northerly dip 

 aU along the northern margin of the granite ; so that on the N.E. 

 margin, the Andesitic Group is seen dipping away from the junction 

 of the Andesitic and llhyolitic Groups, as represented on the map. 

 The absence of the Stockdale Shales indicates the existence of a 

 strike-fault running between the Coniston Elag and Coniston 

 Limestone series. This fault has been recently described by one 

 of us, in a joint paper with Prof. Nicholson, as running across the 

 district *. 



* See Quart. Journ. Geol. Soc. vol. xliv. (1888) pp. 662 et seqq. 



