520 Geological Society : — 



knowledge of the palaeontological details, has fully sustained the 

 results of the author's previous investigations. The rapid attenua- 

 tion and final disappearance of the Speeton Series in a westerly- 

 direction in Yorkshire is discussed, and though the available 

 evidence is held to be insufficient to demonstrate the exact conditions, 

 it is stated that, contrary to the accepted view, the lower zones are 

 probably the first to die out and are overstepped or overlapped by 

 the higher divisions, since at Knapton, 14 miles inland, only the 

 upper zones of the coast-section can be proved to occur, as shown 

 by the presence of marls with Bel. minimus passing upward into 

 the Red Chalk, and by the fossils preserved in the old collections 

 including Eoplites Deshayesii under the name of Amm. Jcnaptonensis, 

 Bean MS., and a few others of the same zone. 



The ferruginous sands locally occurring beneath the Red Chalk 

 on the western edge of the Yorkshire Wolds are recognized as 

 agreeing in all respects with the Lincolnshire Carstone ; and Mr. A. 

 Strahan's conclusions as to the relations of this division to the Hed 

 Chalk are confirmed both in Yorkshire and in Lincolnshire. 



In Mid-Lincolnshire all the palaeontological zones of Speeton are 

 identified and traced, the presence of the leading zonal types of the 

 cephalopoda readily establishing the general correlation proposed 

 by Prof. A. Pavlow and the author, in spite of the greatly modified 

 lithological aspect of the deposits and the corresponding modification 

 of their fauna. The chief features of this correlation, which differs 

 in many respects from that adopted by Prof. Judd and the Geological 

 Survey, are as follows : — 



Speeton. Lincolnshire. 



RED CHALK. 



Zone A. Passage Marls = Carstone (? in part or wholly). 



B. Zone of Bel. brunsvicensis = Tealby Limestone and its southerly 



equivalents (also ? the lower part of 

 the Carstone). 

 C, Zone of Bel. jaculum = Tealby Clay of the Wold escarpment 



(the lower portion of the zone 

 doubtfully represented). 



D. Zone of Bel. lateralis = ' Tealby Clay ' of the outliers west of 



Spilsby (Hundleby Clay), Claxby 

 Ironstone, and Spilsby Sandstone. 



E. ' Coprolite-bed ' = Nodule-bed at the base of the Spilsby 



Sandstone. 



Ximeridge Clay. 



In Lincolnshire, in at least one instance, the synchronal boundary 

 as indicated by the limits of a palaeontological zone is shown not to 

 pursue the same stratigraphical horizon throughout its course, 

 proving that sediments of different character were accumulated 

 simultaneously in comparative proximity to each other. The 

 inherent divergence between the stratigraphical and palaeontological 

 methods in geology is thus once more illustrated. 



The derivative character of the band of phosphatic nodules at 



