Vol. 57.] PEXDLESIBE GEOTJP AT PENDLE HILL, ETC. 363 



Mr. J. R. Dakyns, who surveyed the district in which the knolls 

 occur, says ^ : — 



*We liave, moreovev, independent evidence that the surface of the hraestone 

 underneath the overlying shales and grits is uneven. On Simonseat, a Mill- 

 stone Grit fell on the east side of theWharfe, there are some swallow-holes, 

 which show that the limestone is present at no great distance below the surface: 

 but below Thorpe Fell is a thickness of at least 450 feet of shales overlying 



the limestone It does not seem possible that swallow-holes 



should be formed into limestone through anything like 400 feet of shale ; it is 

 more than probable that under Simonseat the limestone is much nearer the 

 Millstone Grit than it is in other places : that is, the limestone-surface is very 

 uneven.' 



There may, of course, be some unevenness of the limestone- 

 surface, but the facts observed by Mr. Dakyns point rather to 

 the rapid thinning-out of the Pendleside Group here : between 

 Burnsall and Greenhow, little or no measures separate the grits 

 from the limestone ; also in the Nidd Yalley and Upper Wharfedale, 

 the grits are separated by only a few feet of measures from the 

 limestone below. For instance, in the ISTidd Yalley at Lofthouse 

 the following section is exposed : — 



Feet. Inches. 

 Millstone Grit. 



Black laminated limestone 5 



Shale 1 2 



Blue limestone 6 



Shale, with thin band of limestone. 4 6 



Massive limestone. 



We have not been able to search these limestones for fossils, but it 

 would seem not improbable that the whole of the Pendleside Group 

 is represented by these few feet. 



Sections examined for us by Mr. H. B. Muff, F.G.S., in the River 

 Wharfe just below Burnsall Village and in the small beck called 

 Waterspout, south-west of Burnsall, showed shales and limestones 

 with Pendleside fossils. 



On the north side of the anticline, beds of shale with soft dark 

 limestone are seen in the southern bank of the Wharfe, immediately 

 south of the Linton stepping-stones, also with Pendleside fossils, 

 and traces of a similar fauna occur in the shales near Hebden in 

 Wharfedale. 



That the Carboniferous succession of South Craven differs very 

 considerably from that seen in the flanks of Ingleboro', Penyghent, 

 and the fells in the upper part of Wharfedale is apparent ; and it is 

 commonly taught that the change of the southern into the northern 

 type is sudden and without any gradual passage from one to the 

 other. It is also believed that this sudden change occurs and is 

 connected with the great east-and-west system of faults called the 

 Craven Faults. Mr. Tiddeman has advanced the view that the 

 change was entirely due to the fact that the Craven Faults were in 

 existence and in process of development during the deposition of 



1 Quart. Journ. Geol. Soc. vol. Iv (1899) pp. 360-61. 

 • Q. J. G. S. No. 227. 2 c 



