OF THE SWISS JUKA. AND ENGLAND. 



239 



Pterocerian or Kimeridgian. — The classical locality for this 

 stage is Banne, near Porrentruy, where it has been known and 

 worked for many years. Its lithe-logical character is very constant 

 in the district, being composed of well-bedded limestones usually 

 very fine in texture and light coloured ; there are also some thin 

 beds of marl present, and these are usually very fossiliferous. The 

 limestones are much quarried for building-purposes. 



The quarries at Delemont are opened in rocks belonging to this 

 stage, and here the following section was observed : — 



Compact grey limestones ~ 



Fossiliferous marly bed £ ^ 



Thick-bedded limestones 



Compact limestone * , 



Most of the fossils obtained in this locality come from the marls, 

 because, as a general rule, the compact limestones are not fossili- 

 ferous, and when they are so, it is almost impossible to get the 

 fossils out in a determinable condition. 



The section at Vorbourg, in the Pterocerian, shows compact 

 limestones of much the same character as the beds in the quarries 

 below, and described in the above section. 



At Glovelier similar beds were also seen ; and in a small expo- 

 sure at the roadside, a little to the west of the village, the surface 

 of one of the limestone beds is exposed, which is crowded with 

 Pteroceras, &c. 



Limestones like those of Delemont were seen at Courrendlin and 

 also at Vermes ; but in the last-named locality the beds were some- 

 what nodular. 



In the neighbourhood of Porrentruy these beds have been, as 

 already stated, largely worked. They are also quarried a little to 

 the north of Yillars, where about 20 feet of the limestones are shown, 

 the uppermost part being fossiliferous. 



The fossiliferous Pterocerian marls are also exposed at the road- 

 side between Fontenois and Bressancourt, and again at Courgenay. 

 In both these localities the rock is crowded with fossils. 



Subjoined is a list of the fossils, which come chiefly from the 

 marls : — 



Pterocerian Fossils. 





Delemont. 



0Q 

 •i-H 



o 

 a 



CD 



■+3 

 fl 



o 

 ft 



j Courgenay. 



Glovelier. 



Nautilus Marcouanus, D' Orb 







* 































* 



* 



Rostellaria Wagneri, Thurm 











Pholadomya myacina, Ag 







-;c- 





Protei, Ag 



* 





* 





multicosta, Ag 









* 



