160 Dr. Wheelton Hind — The Yoredale Series. 



and the series of shales and sandstones above which occur in 

 South-West Yorkshire, Lancashire, Cheshire, North Staifordshire, 

 and Derbyshire. For, although this series of shales and sandstones 

 appears to occupy an analogous position between the thickest 

 bed of limestone in North- West Yorkshire or the massif of 

 limestone in Derbyshire, and the base of the Millstone Grits, 

 respectively, the intervening series in each case differs essentially, 

 both lithologically and palcEontologically ; and in my opinion these 

 two series, which have been so long confounded together under one 

 common term, are totally distinct, and really form the key to the 

 Carboniferous sequence in Great Britain. 



It was unfortunate that Professor Phillips adopted the term 

 Yoredale Series for one of the main subdivisions of the Carboniferous 

 system, although the term was undoubtedly applicable for a local series 

 of rocks in Wensleydale, etc., which exhibited a gradual but marked 

 change in lithological type from those immediately below them ; 

 although there is no doubt that he was aware that the Yoredale Series ^ 

 was only the local equivalent of the upper part of the Carboniferous 

 Limestone, yet he insisted on correlating the beds with those which, 

 in a different area, were undoubtedly above the massif of limestone. 

 A single quotation ^ will suffice to show Professor Phillips' view 

 as to the relations between the massif of limestone and his Yoredale 

 Series : "The great limestone series which at Greenhow Hill is one 

 mass, admits between some of its upper members partings which 

 are thin at Grassington and Kettlewell, but towards the W., N.W., 

 and N. augment in thickness and assume new characters." This 

 statement is important, because it is based on the stratigraphical 

 facts ; and it is this splitting up of the upper pari of the mass of 

 limestone by beds of shale, with intercalations of sandstone further 

 north, which gives rise to the succession of beds in Wensleydale, 

 where they have received the name Yoredale Series ; the term should, 

 however, only be retained for these local beds, because they are 

 typical only of a limited area. 



But at the same time it follows that it is erroneous to regard 

 the Yoredale beds as superimposed upon the Carboniferous Limestone, 

 for they are, unmistakably, the direct equivalents of each other ; and 

 that such is the case can be shown on the strongest paleeontographical 

 and stratigraphical evidence. In the briefest possible way, I will 

 indicate the evidence from the ground itself. One great but 

 important objection to the use of the term Yoredale Series in any 

 other but a local sense, is the uncertain and arbitrary line adopted 

 as its base. In North-West Yorkshire the Great Scar Limestone was 

 taken as the upper limit of the Carboniferous Limestone ; but this 

 limestone, although in Wensleydale somewhat massive, when traced 

 north splits up and undergoes marked lithological changes, and 

 becomes the Melmerby Scar Series. The Hardraw Scar Limestone, 



1 " Geol. Yorks.," pt. ii, pp. 19, 27, 32, 33, 34, and 61, pi. xxiii, Nos. 9 and 10 ; 

 pi. xxiv, sections 3 and 24. 



2 p. 32. 



