Vol. 57.] PENDLESIDE GEOUP AT PENDLE HILL, ETC. 361 



had often come down to it when digging. The shales of Flashy 

 Fell are of interest, because it was here that Phillips obtained some 

 of his goniatites. We found fossils of the Pendleside fauna in 

 abundance, in the shales and limestones just above Thorlby but the 

 majority were much crushed. The beds in the gill in Sulber 

 Lathe and m the stream north of Plasby Hall have similar fossils. 



The ' Knoll ' Area of Cracoe and Thorpe. 



Extending from Greenhow on the east to beyond Cracoe is a 

 stretch of country exhibiting very striking and peculiar contours • 

 m it appears a more or less linear series of rounded limestone- 

 knolls which have already been very fully described by Mr Dakvns 

 Mr. Tiddeman, and Mr. Marr. It hardly forms part of the scheme 

 of this paper to enter into the discussion concerning the origin of 

 these structures, but it is imperative that we should record our 

 opinion as to their horizon. 



Mr. Tiddeman has taught for many years that the limestone 

 which forms the knolls m this area is on the horizon of the Pendle- 

 side Limestone, and that it formed original reefs on the latter 

 subsequently surrounded and enveloped in shales. This view of 

 the horizon of the ^knoll-limestone' has been accepted and 

 followed by other geologists and palaeontologists, with the result 

 that the fossils which occur in it have been assigned to the Pendleside 

 Limestone. For our part, however, we are quite unable to believe 

 that the knoll-limestones of this area are Pendleside Limestone; on 

 the contrary, we are of opinion that they are part of the upper beds 

 of the massive limestone, which, even so near as Clitheroe and 

 Downham, Mr. Tiddeman admits to have formed knolls of precisely 

 identical character with similar fossils. We have founded this 

 opinion on both stratigraphical and pal^ontological grounds. 



The occurrence of well-bedded with massive, obscurely-bedded 

 limestone is not peculiar to this district, but is a fairly common con- 

 dition of the upper portion of the undoubted Mountain-Limestone 

 tracts of Clitheroe, North Staffordshire, and Derbyshire. Li each of 

 these districts the obscurely-bedded limestone has the same lithological 

 characters, andweathers in the same manner into knoll-like hills. ^'We 

 can find no evidence for the assumption that these rest on the Pendle- 

 side Limestone, for nowhere is the base of the knoll-forming limestone 

 seen ; on the other hand, limestones of the Pendleside Group mav 

 be observed, resting in their natural position upon them. For 

 example, in the depression between Butterhaw and Skelterton, in a 

 fairly large swallow-hole (one of a series which marks the junction 

 of the shale and limestone), we find shales and limestones dipping at 

 an angle which would carry them over the limestones of the knoll. 



The palaeontological evidence is no less clear, and even more satis- 

 factory. The fossils of the Cracoe knolls present a facies identical 

 with those of Clitheroe, Castleton, or Thorpe Cloud in the Carboni- 

 ferous Limestone (see Appendix A, facing p. 402) ; . while in the shales 

 resting upon them, in the swallow-hole mentioned above, we found 

 Posidoniella Icevis, Posidonomya Becheri, and Glyx>hioceras retlcu- 



