320 MR. W. HILL ON THE LOWEH BEDS OF THE UPPER 



26. On the Lower Beds of the Upper Cretaceous Series in Lin- 

 colnshire and Yorkshire. By William Hill, Esq., P.G.S. 

 With the Description of a Xew Species of Holaster, by A. J. 

 Jukes-Browne, Esq., E.G.S. (Eead April 11, 1888.) 



[Plate XII.] 



Until recently no attempt had been made to describe the zonal 

 divisions of the lower beds of the upper part of the Cretaceous series 

 in Lincolnshire. Indeed, Prof. Judd remarked in 1869, " The time 

 has not yet come for separating the great mass of the Chalk forma- 

 tion in this county into zones, .... such a task not having been 

 accomplished in the best-explored districts of the Chalk " *. 



In 1876 Dr. Charles Barrels t, having been unable to visit this 

 county, follows, in his well-known work, the description given by 

 Prof. Judd. It was not until the publication, in the spring of 1887, of 

 the " Greology of part of East Lincolnshire," a memoir of the Geological 

 Survey, that a systematic attempt was made to correlate any part of 

 the Chalk of Lincolnshire with that of the more southern counties of 

 Cambridgeshire, Hertfordshire, &c. 



But the author of this memoir laboured under a disadvantage ; for, 

 as he remarks (p. 28), " The zones of the latter county [Cambridge] 

 have not yet been traced northward into Norfolk, where the Chalk 

 begins to put on what may be termed the northern or Lincolnshire 

 facies ; the data requisite for the proper correlation of the two areas 

 are therefore incomplete." And again (p. 31), " As yet we know 

 nothing of the changes which the Chalk zones undergo in their passage 

 from Cambridge to I^orfolk ; and in the absence of this connecting 

 stratigraphical evidence, the correlations now suggested are not to be 

 rer-eived as a decided expression of opinion." 



But while this memoir was in the press, Mr. Jukes-Browne 

 and myself undertook the investigation of the lower part of the 

 Chalk in Suffolk and Norfolk, the results of which have already 

 been published J. 



"We therefore now possess that connecting-link of stratigraphical 

 evidence which was wanting when my friend and colleague in the 

 Norfolk paper completed the Memoir for the Geological Survey on 

 East Lincolnshire ; and it seemed to me almost as much a duty as a 

 pleasure to carry forward the knowledge obtained by the study of 

 the Chalk in Suffolk and Norfolk, and apply it to the same series of 

 the Cretaceous system in Lincolnshire and Yorkshire. 



The Chalk of Yorkshire has been the subject of several papers. 



The Eev. Prof. Wiltshire § has given a brief description of the 

 Speeton cliffs, written before the main divisions of the Chalk were 



* Prof. J. W. Judd on "The Lincolnshire Wolds," Q. J. G. S. toI. xxiii. p. 235. 

 t C. Barrois, " Eecherches," &c. Mem. Soc. Geol. du Kord, vol. i. p. 189. 

 J " On the Lower Beds of the Upper Cretaceous Series in Suffolk and Norfolk," 

 by A. J. Jukes-Browne and W. Hill, Q. J. G-. S. vol. xliii.p. 544. 

 § Wright's ' Mon. Brit. Fossil Cretaceous Ecliinodermata,' p, 8. 



