100 J. E. Marr — The Coniston Limestone Series. 



relationship of the fauna of this series to that of the overlying 

 Applethwaite Series. 



The last exposure of the Yarlside rhyolite to the west occurs on 

 the moorland above the Stile End beds, and in sections lying further 

 west, the Applethwaite and Stile End beds are separated only by the 

 conglomerate. The conglomerate has not been detected in the Stile 

 End section, but the Applethwaite beds consist, as usual, of ashy 

 calcareous shales, with bands and nodules of impure limestone. Tu 

 the course of a small stream flowing towards Sleddale, and a little 

 below the watershed, the Stauroceplialus Limestone is seen faulted 

 against the Skelgill beds of the Stockdale Shales, so that the Ashgill 

 Shales are here cut out. 



Many exposures of the Coniston Limestone Series are seen in the 

 small valley running from the Garbourn Pass to Kentmere, occupied 

 by the stream known as Hall Gill, and they contain abundant fossils^ 

 but the ground is much faulted, and it is difficult to make out the 

 subdivisions. 



On Applethwaite Common, also, the conglomerate has not been 

 detected, and consequently it is impossible to assert positively that 

 the representatives of the Stile End Group are present The Ash- 

 gill beds are found here, but their relationship to the Applethwaite 

 series is not clearly shown. The beds of the latter series, as is well 

 known, here contain abundant fossils. The highest beds of this- 

 series consist here of fairly pure limestones. 



We now arrive at the important sections of the tract of country 

 lying between Troutbeck and Windermere, the principal one being 

 developed in Skelgill Beck and its tributaries. 



Here, again, the conglomerate has not been seen, so that, although 

 the beds seen in a quarry north-east of the 'Upper Bridge' over this 

 stream strongly resemble the Stile End Beds, I am not prepared 

 to assert that they belong to that series rather than to the Apple- 

 thwaite series. 



The beds of the Applethwaite Series consist mainly of calcareous, 

 very fossiliferous, shales, with limestone bands, but a feature is here- 

 clearly seen, which probably characterizes also this series in the 

 more obscure sections to the east. I refer to the existence of a 

 white horny limestone at the very summit of the series. This is 

 seen in the stream at the Upper Bridge, and the Staurocephalus 

 limestone reposes directly upon it. No fossils have been extracted 

 from this bed, but a number of large Orthocerata are seen in cross 

 section in the bed of the beck. Such Orthocerata occur at Keisley, 

 and it is possible that the Keisley limestone, which contains on the 

 whole the fauna of the Applethwaite Limestone, along with some 

 forms which are not known to occur nearer than the Chair of 

 Kildare, is the highest subdivision of the Applethwaite Series. I 

 wish to discuss this point at some length, because an important 

 physical problem is connected with it. A similar limestone is found 

 in Swindale Beck in the Cross Fell area, and was referred by Prof. 

 Nicholson and myself to the Staurocephalus Limestone, on account 

 of the occurrence of the fauna of that limestone in the associated. 



