﻿Vol. 6 1.] BLEA WYK.E BEDS IN NORTH-E1ST YORKSHIRE. 455 



The total thickness of the Dogger at Postgate Hill is about 12 feet, 

 practically all ironstone, but it is too poor in quality for profitable 

 working under present industrial conditions. 



Fossils are very numerous, both in species and individuals ; but 

 the preservation is poor, nearly all occurring as internal casts only. 

 I have been able to identify the following : — 



Acrosalenia sp. 



Rhynchonella cynocephala. 

 Rhynchonella subobsoleta. 

 Rhynchonella subtetrahedra. 

 Terebratula spheroidalis. 

 Terebratula subraaxillata. 

 Terebratula trilineata. 



Lima cardiiformis. 

 Hinnites velatus. 

 Gervillia Hartmanni. 

 Gervillia lata. 

 Gervillia tortuosa. 

 Gresslya peregrina. 

 Trigonia denticulata. 

 Trigonia striata. 



Astarte elegans. 

 Modiola aspera. 

 Ostrea flab ell o ides. 

 Ostrea solitaria. 

 Pinna cuneata. 

 Cera my a bajociana. 

 Cardium acutangulum. 

 Cardium gibberulum. 

 Cardium striatulum. 

 Quenstedtia oblita. 



Nerinaa cingenda. 

 Nerita costata. 

 Turbo 0). 



Serpula deplexa. 



The commonest forms are Terebratula trilineata, T. submaxillata, 

 and Hinnites velatus. 



The most noteworthy feature of this fauDa is the abundance of 

 brachiopods and lamellibranchs, and the rarity of gasteropods. The 

 occurrence of Terebratula trilineata and Nerincea cingenda in the 

 same bed is sufficient to show that we are here dealing with a con- 

 densed representative of a much thicker series in the coast-section, 

 where the Terebratula-Bed and the Nerincea-Bed are separated by 

 26 feet of yellow sandstone. The general character of this assem- 

 blage of fossils likewise suggests that it represents only the upper 

 part of the Blea Wyke section, that is, the Dogger proper and the 

 Yellow Beds. It appears, therefore, that even in this, the most 

 complete inland section, the Serpula- and Lingula-Beds are unrepre- 

 sented, and there is no sign of any gradual passage upwards from 

 the Lias. 



My thanks are due to Miss M. Keighley, of Spring-Hill House, 

 Whitby, for kindly allowing me to examine her large collection of 

 fossils from this locality. 



V. The Noeth- Western District. 



Along the north-western escarpment of the Cleveland Hills, from 

 the sea-coast to the neighbourhood of Battersby and Burton Head, 

 a distance of some 20 miles, the Dogger can hardly be said to exist 

 as an independent bed ; but about the head of Bilsdale it again 

 becomes conspicuous. 



Just below the singular group of blocks of sandstone known as 



