356 Hughes — Geology of the Lake District. 



Coniston Flags proper, in which are the great quarries, Wliere the 

 hedding and cleavage nearly coincide they form good flags, where 

 the cleavage makes a considerable angle with the bedding they split 

 along the cleavage ; but the lines of bedding are well marked 

 across, and the stone breaks into irregular slabs of hardly any value 

 except as " troughs " for walling. 



The thickness of these beds is about two thousand feet. Fossils, 

 with the exception of Orthoceratites and Graptolites, are very scarce. 

 I, however found the following ; quite enough to connect them with 

 the beds above, instead of with those below : — 



Favosites fibrosa. 



^ctinocrinus pulcher. 



Graptolites Ludensis. 



G=. sp. 



Pterinea tenuistriata ? 



Cardiola inter rupta. 



A.6. 4. Tough grit or greywacke, with a few subordinate flaggy, 

 or slaty beds. These are the highest beds seen in the Horton 

 district. I have estimated their thickness at about twelve hundred 

 feet on Casterton Fell. I have found no fossils in them there, or in 

 the Horton district ; but fossils rarely occur in rock of that character, 

 Near Cautley Spout, north-east of Sedbergh, I found a large Lituites 

 in a tough grit, which I must refer to the top of this, or the bottom 

 of the overlying set (A.&. 3). Also, at Helmside, near Dent, there 

 are some flaggy beds, near the top of what I take to be this grit 

 which have yielded the following : — 



Lituites giganteus. 

 Orthoceras primcevum. 

 0. suhundulatum. 

 0. sp. {ventricosum ?) 

 Worm tracks, etc. 



Cliona. 



Spirorbis Lewisii. 



Geratiocaris Murchisoni (See Geol. 



Mag. Vol, III, p. 203). 

 G. robustus. 



Fterinea tenuistriata. 

 Gardiola interrupter.. 

 Orthoceras Ludense. 

 0. bullatum. 

 0. angulatum. 

 0. 3 other sp, 

 ©. sp. 



A,&, 3. These are the sandy slates of Casterton, Middleton, and 

 Howgill Fells — more than 3000 feet thick. Having already 

 described them in the first mentioned locality, I will now only give 

 a list of fossils, to show that as a group they are the same as those 

 which occur down to the bottom of the Flags, 

 Petraia. Graptolites. 



Encrinites. Tteriiiea tenuistriata. 



Geratiocaris Murchisoni. Cardiola interrupta. 



G. robustus, Lituites. 



Acidaspis. n, sp. Salter. Orthoceras, 2 sp. 



Fhacops, sp. 

 Thus it appears that all (A.) is one series, characterized by such 

 fossils as Cardiola interrupta, that it rests unconformably on a lower 

 series (B,), characterized by such fossils as OrtJiis Actonice and 

 Trinucleus. 



1 gather from Prof, Sedgwick, whose kind help on all occasions I 

 take this opportunity of acknowledging, that A.c, 1 to A.c, 4, are 

 what he included under " Coniston Flags," and I would therefore 

 merely wish to return to the classification which he published in 

 1B46, and make the flags so defined the base of the Upper Silurian 

 Series. 



