FAUNAL SUCCESSION OF THE UPPER BERNICIAN 629 



Brachiopods. — Productus giganfeus, Martin's typical form, 

 is common. 



Faunal List. 



Cycloph3-lIum aff. pachy- 



endothecum, Thom. 

 Aulophyllum 

 Cyathophylloid Clisiophyllid, 



genus nov. 

 Lithostrotion junceum (Flein.) 

 Seminula ambigua (Sow.) 



Latissimoid Producti (Productus ^8) 

 and variants 



Productus aff. aculeatus (Mart.) 

 Productus giganteus (Mart.), very 



large specimen 

 Productus semireticulatus (Mart.) 

 Euomphalus pentangulatus, Sow. 

 Edmondia sulcata, Phill. 



Notes. — Productus giganfeus : this very large variety is 

 identical with those abundant in the Yoredale Limestones in 

 Wensleydale and Swaledale, and closely resembles the figure 

 in Davidson's Monograph, plate 38. The variety is finely 

 ribbed, but the pedical valve has strong marginal folds, and 

 the shell is very thick. 



Fell Top Limestone. 



Geographical Distribution. 



The bed outcrops in Allendale and Hexhamshire. It passes 

 beneath the Tyne in the neighbourhood of Bywell, but is not 

 exposed. It runs N.N.E. by Harlow Hill, Stamfordham, and 

 Mitford, and reaches the coast near Alnmouth. 



Stratigraphical Characters. 



Between the Tyne and the Pont the Fell Top Limestone is 

 at least 20 feet in thickness, and consists of three calcareous 

 beds separated by two argillaceous horizons. At Alnmouth 

 it is represented by two thin seams of limestone, 18 inches and 

 9 inches respectively, divided by 6 inches of shale. 



Faunal Diagnosis. 



Corals. — Dibunophylluni muirheadi (mut. cf. Dib. ij/) and 

 Phillipsastrcea radiata plentiful and characteristic ; Litho- 

 strotion junceum prolific, and Lithostrotion portlocki Bih\x\\(la.\\t', 

 Cyathophylluni regiuni, towards Cyathophyllum <f), not un- 

 common. 



Brachiopods. — Latissimoid Producti (Prod. /3) and varieties 

 exceedingly abundant. 



