Miss Eyton — Age of the Western Counties Clay. 547 



the latest general submergence, as sliown by Messrs. Harmer and 

 Searles Wood, in their paper read before the British Association at 

 Norwich ; and that consequently all the overlying marine beds belong 

 to the period of emergence, or may be accounted for by minor and 

 partial submergences. 



The term " Glacial," applied to these beds, is somewhat vague. 

 The period of glaciation in the Northern and Midland counties must 

 have extended into comparatively recent times when the land had 

 for the most part risen above the retiring waters, for we find striated 

 and travelled fragments in beds of much later date than that we have 

 been considering. But if the term " Glacial" is to be restricted to 

 those beds which were deposited during the progress of the great 

 submergence, as distinguished from those which vv^ere formed after 

 the emergence commenced, then the blue clay must be held to be 

 the latest glacial bed, notwithstanding the evidences of ice-action 

 which occur on a later horizon. It would be well to arrive at a 

 definite conclusion on this point, as well as on the use of the term 

 Boulder-clay, as it may be the source of some confusion, especially 

 to the unlearned. 



The accompanying table shows the position of the drift-beds in 

 the Eastern and Western counties relatively to each other and to the 

 period of the greatest general submergence ; supposing the position 

 assigned to the blue clay to be the true one, the rest necessarily 

 follows. 



TABLE SHOWING THE RELATIVE POSITION OF THE MARINE DRIFTS IN THE 

 EASTERN AND WESTERN COUNTIES. 



Eastern Counties. Western Counties. 



The Hessle clay and gravel lies some- 

 where near this horizon. Also the Kelsea 

 Hill beds with Cyrena Jluminalis, a species 

 never found in the Western counties. 



Esker or re-assorted drift. 



Eed clay with travelled and striated 



Shell-hearing sands and gravels, con- 

 taining none hut living species in con- 

 nexion with mammalian remains. 



Period of the greatest submergence. 



Purple clay without chalk of York- 

 shire, etc. 



Blue clay without chalk, passing at 

 Eugby into 



Purple clay with chalk, or Great 

 Boulder-clay of the Eastern counties. 



Blue clay with chalk. 



Middle Glacial sands and gravels, con- 

 taining extinct species and genera. No 

 mammals. 



Gravels underlying the blue clay. The 

 exact horizon is doubtful. 







Lower Glacial beds. 





