lIFE-ZONfiS IN THE BRITISH CARBONIFEKOUS KOCKS. oOo ' 



The Teilia Quarry contains the following fauna and flora : — 



Posidonomya Bcoheri. Olijphloceras rcticulatum. 



Posidonieila Iccvis. / Prolci-anites comj/rcssuf. 



rtcrinoj)ccten pajiyraceui, Orth'icuras sp. 



■„ car'hnlariHS. llhijnchoncMa afL frilatcra. 



Adiantitcs antiqiiiis. fiphenopteris affinis. 



Kp]icno2)teris Teiliana. Itachoptcris glahdlata. 



„ suhgeniculata. „ inequilatera. 



„ striata. ? Archcopteris sp. 



,, pach\iracliix. Axtcrocrlamitci scroMcid-.itns. 



,, var. stenophi/Ua. LepldopJdvios sp. 



„ Schlcbaui. 



Here, apparently, without unconformity, the Cyalhaxonia beds are 

 immediately succeeded by the Pendleside Limestones without any cherty 

 series, and the Teilia Limestones here are more calcareous and contain less 

 carbonaceous matter than the Holywell shales further east. 



Traced northwards towards Prestatyn we find Posidonomya Be.cheri 

 beds succeeding the Cyadiaxonia beds of Prestatyn, which are white in 

 colour and not at all like the 'Aberdo' limestones of Treloggan or 

 Grange Quarry ; but the fossils indicate very markedly their real horizon 

 and homotaxis. 



At Prestatyn the series is as follows : — 



1. Pendleside limestones, about 70 feet thick, with P. Becheri and 

 Pterinopecien 2Japy'>'aceus. 



At the base : — 



2. Cyathaxonia beds with P. rjigantcus. Practically free from chert 

 or siliceous replacement. 



3. A series of black limestones then bedded and not very fossiliferous. 



With Zapkrcnth aflE. cnnisltillcni, Cavi]}op})yllum Derhicnsc, Productus longi- 

 Spinns, Martiniii rjlahra. 



These black limestones cannot be the equivalents of the Teilia lime- 

 stones, but are far below them. They probably belong to the lower part 

 of the Upper Dibunophyllum zone. The most striking point at Teilia 

 and Prestatyn is the absence of the thick chert series, so well developed, 

 only one mile to the east. 



Another fine exposure of the Posidonomya beds is at Lady McLaren's 

 quarry. The lower beds are rich in fossils, the most common being 

 Pterinopecten papyraceus, but some plants similar to those which were 

 found at Teilia occur here. The very lowest bed exposed contains 

 Cyathaxonia and Amplexi-zuphrentis. A few yards west the Cyathaxonia 

 beds are seen in another quarry, demonstrating that the same succession 

 occurs here that obtains on the other side of the hill at Gwaerysgor 

 and Teilia. Walking east from Lady McLaren's quarry outcrops of the 

 Posidonomya beds occur at intervals as far as Top Nant Farm. East of 

 the farm is a shallow sinking, from which Po'sidonomya limestones have 

 been got ; higher up the hill a shallow cutting shows smashed chert 

 debris, making it appear that here some cherts lie above some of the 

 Posidonomya limestones ; but the junction is not seen, and the idea that 

 the pits have been trials for lead along a fault is not impossible. About 

 a quarter of a mile north is a quarry in chert at about 200 feet above 

 CD., the chert E. of Top Hant Farm being 450 feet above O.D. 

 1906. X. 



