42 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [DeC. 3, 



(5.) Over the preceding group comes a series of beds (fig. 2, a\ a) 

 wliich, with numerous undulations, breaks, and partial changes of 

 strike, descend to, and pass under, the Carboniferous Limestone. The 

 rocks are in many places deeply covered by the bog-earth of the 

 mountains ; but some beds are seen in the watercourses with a good 

 transverse cleavage, and among them are some old deserted slate- 

 quarries, in which the cleavage-planes are beautifully marked by the 

 laminse of deposit. The slates were found to be worthless ; as, in- 

 deed, is generally the case where the laminae of deposit are very 

 near together on the cleavage-planes. The slates are repeated by 

 undulations ; and in a deep watercourse, called Lang Gill, we found 

 associated with them a fine conglomerate with calcareous concretions 

 and numerous veins of calc-spar. Pheenomena of a similar kind 

 are found in Howgill Fells ; and the whole group deserves notice, as 

 it is in the exact geological position of the well-known Ireleth slate- 

 quarries. Farther down (in a watercourse called Gaze Gill) were 

 numberless alternations of coarse grit and slate (fig. 2, a) . This system 

 was much broken, the strike was continually shifting, and the beds 

 were sometimes very highly inclined. On reaching a still lower level, 

 the prevailing dip was about N. or N. by E., and the beds became 

 gradually less inclined as they descended towards the limestone. In 

 this part of the series were some beautifully striped slates ; and 

 among the more earthy beds were some rare instances of septarian 

 balls with calcareous ^^eins. The only fossil found among them was 

 a specimen of Graptolites Ludensis. 



Making a traverse over the moor-lands, and descending from the 

 old slate-quarries above-noticed by Wygarth Gill, there is a still better 

 section of the group under notice. The beds immediately overlying 

 the quarry-rock are concealed, but in Wygarth Gill we first found a 

 series of brown and rather earthy flagstones, alternating with whet- 

 stone-slate and with masses of hard blue flagstone containing concre- 

 tions more or less calcareous. Farther down are beds of hard grey 

 gritstone, alternating with flagstone. The beds are repeated by nu- 

 merous undulations, but gradually acquire a more steady dip, nearly 

 true north, and at an angle of about 60°. In the flagstones of this 

 part of the series are many fossils, which, as a group, are perfectly 

 identical with the fossils in the corresponding beds (over the hard 

 grits) in Howgill Fells. We have here the beautiful small Pterinea 

 tenuistriata of Howgill Fells in very great abundance. Among the 

 fossils was a new species of Aspidaria, which will be figured in the 

 * Cambridge Fasciculus,' now in the press. 



I had never before examined this line of section, which is, on se- 

 veral accounts, of great interest, as it cuts through the north-eastern 

 protuberance of Eavenstonedale Fells, where two lines of elevation 

 (one striking about N.N.E., and the other nearly east and west) run 

 together. The beds above-described seem to have been broken, 

 crumpled up, and contorted between these two axes of disturbance ; 

 producing that protuberance in the mountain-cluster, round which 

 the carboniferous limestone of Ravenstonedale is wrapped, after it 

 diverges (towards the N.W.) from the line of the Craven fault. 



