TDK JURASSIC SYSTEM 453 



feet thick, consisting of dolomitic limestones containing Cyrena 

 ni<i<>*t, I'ni-liulu inflexa, and other marine species, the upper being a 

 1'i-u tfrt <>(' marl with brackish and freshwater fossils; and these 

 beds pass up into the Valenginian, which is classed as Lower 

 I'lviutvous, but may represent the highest part of our Purbeckian 

 a< \\vll u M'nii- uf the Wenlden. 



2. Germany 



The Upper Jurassic Series is well developed in Hanover, and 

 extends westward into Westphalia beneath the Cretaceous deposits. 

 The succession established by the labours of Seebach and Credner 

 has been compared with the English Series by Dr. C. Struckmann, 

 and the following table is compiled from his memoir, a translation 

 of which will be found in the Geol. Mag. for 1881, p. 546. 



Tort- J Mundennergel, gypriferouB marls / Lacustrine Be(ls< 

 landian ~\ Plattenkalk ot'Einibeckhauser (platy limestones). 



I Limestones and marls with Perisphinctes gigas. 

 Kime- I ^ irgula Beds, compact and oolitic limestones. 

 ril"iai Pteroceras Beds, limestones with Harpagodes Oceani. 



I Nerincea Beds ( = Astartian), limestones. 

 Corallian f UPP er Cor. limestones (zone of Pecten varians). 



\ Lower Cor. limestones (zone of Ostrea rastellaris). 

 Oxfordi 1 n ' "Hersumer Beds. Sandy beds with Aspidoceras perarma- 



^ turn, Cardioceras cordatum, and Gryphcea dilatata, 

 ,,ii .. ( Clays with ornatus Ammonites. 



" ( Macrocephalus Beds, clays and ironstones. 



It will be seen that the greater part of the series consists of 

 limiT-tones with some clays at the bottom and a remarkable 

 development of marls near the top ; these are of red and green 

 colours and much resemble the marls of the Keuper ; they are 

 from 400 to 500 feet thick in Hanover, but thicken westward 

 to over 1500 feet in Westphalia, where they include limestones full 

 dt I'nrlmln, Vivipara, and Cyclas, as well as beds of gypsum and 

 rock-salt. The Serpulite limestone is full of small Serpula 

 tubes, but aUo contains Corbula. 



In the south of Germany (Swabia and Franconia) the Upper 

 .Fur;t-> ic Series is again found, but has a different pala;ontological 

 t'ari.-s. Its thickness is only from 800 to 1000 feet, and the 

 succession of zones is as below : 



I-v..t. 

 p . fZone of Oppelia steraspis and Perisphinctes gigas, 



\ (Plattenkalk and Solenhofen limestones) ... 80 

 ["Zone of Exogyra virgula, including the coralliferous 

 ,-. I limestone of Nattheim ...... about 150 



V1H1 ' I Zone of Reineckia eudoxus (limestones) .... 100 



I Zone of Oppelia tenuilobata (marly limestones) . .130 



