Succession of Beds below the Millstone Grit Series. 155- 



Many detailed sections are given, showing in each case the exact 

 fossiliferous horizons. The geological succession between the massif 

 of limestone and the Millstone Grit Series on Pendle Hill is shown, 

 by various sections, to contain a characteristic limestone series T 

 easily distinguished by palaeontological and lithological characters 

 from the White or Clitheroe Limestone. The calcareous series is 

 found to be very constant over a certain definite area, and to 

 contain a zonal fauna. 



By various sections the extent of the deposit is shown, and it is 

 demonstrated that the deposit occupies a basin, of which the Pendle 

 district occupies the maximum area of deposit, for the sequence thins 

 out rapidly north-west and south. But although the beds thin out, 

 a calcareous series with a typical zonal fauna is always present. 

 Beds containing this fauna are traced from County Dublin, the Isle 

 of Man, Bolland, Craven, the Calder and Mersey valleys, to Derby- 

 shire and North Staffordshire. It is shown that this series, for 

 which the term Pendleside Series is proposed, occupies a basin 

 about the size of the area indicated above, and that the beds are 

 lithologically distinct from the Yoredale Beds of Wensleydale, and 

 contain a different fauna. 



Part II. discusses the question in detail, from a palaeontological 

 point of view. Several goniatites and Posidonomya BecJteri are 

 shown to be characteristic of the lower part of the series, while 

 Avicidopecten papyraeeus, Posidoniella Icevis, and certain goniatites 

 have a wider distribution in the series. 



The faunas of the Yoredale Beds of Wensleydale and the Pendle- 

 side Series, generally mapped as Yoredales, are shown to be entirely 

 distinct ; and the Yoredale Series of Wensleydale is shown, on 

 palaontological and stratigraphical grounds, to be the equivalent of 

 the upper part of the massif of limestone. 



The migration of certain families of fossils from the north to the 

 south, brought about by a slow change of environment, is shown by 

 tables, and lines called' isodiectic lines ' are drawn to represent this 

 distribution. It is shown that the Nuculidae are found in the lowest 

 Carboniferous beds in Scotland, but come in at successively higher 

 horizons as the beds range southward. 



These facts and comparative thicknesses are the basis of an 

 argument as to the local distribution of land and water in 

 Carboniferous times ; and it as shown that the peculiar change in 

 type which Carboniferous rocks undergo in passing from north to 

 south is due entirely to physiographical conditions, and not to any 

 theoretical assumption of contemporaneous faulting. It is shown, 

 moreover, that the Craven Faults per se have had nothing to do 

 witli this change of type. The correlation of the limestone-knolls 

 of Craven with the Pendleside Limestone is demonstrated to be no 

 longer tenable. 



