ORDOVICIAN BRACHIOPODA 



15 



Onniella and Reuschella, for example, first occur in the Zahorany Formation, 

 Dalmanella in the Letna Formation and Bicuspina and Drabovia in the Liben Forma- 

 tion, which have been dated as Soudleyan, Harnagian and Costonian respectively 

 (Williams in Williams et al. 1972 : fig. 2). Moreover, even so characteristic a 



idard Succession 



Shelve Succession 

 Whittery Shales 



Soudleyan 

 CARADOC 



Whittery Volcanic Gp. 



Hagley Shales 



Hagley Volcanic Gp. 



Harnagian 



Aldress Shales 



Costonian 



Spy Wood Grit 



Upper 



Middle 

 1 1 Awncn n 



Rorrington Beds 



LLMINUtlHJ 



Lower 



Meadowtown Beds 



Upper 



Betton Beds 



Weston Beds 



LLANVIRN 



Stapeley Shales 



Lower 



Stapeley Volcanic Gp. 





Hope Shales 



ARENIG 



Mytton Flags (s.l.) 



Stiperstones Quartzite 



Fig. 2. Classification of the Ordovician rocks of the Shelve area according to the 



brachiopod faunas. 



