THE JURASSIC PERIOD. 



229 



characterised by special life-forms than has as yet been found 

 practicable in the case of any other rock-series. 



GENERALISED SECTION OF THE JURASSIC ROCKS 

 OF ENGLAND. 



Fig. 159- 



Purbeck Beds. 



Portland Beds. 



-Kimmeridge Clay. 



Coral-Rag. 



-Oxford Clay. 



Cornbrash and Forest-marble. 



Great Oolite. 



Fuller's Earth. 



Inferior Oolite. 



-Upper Lias. 



( Middle Lias (Marlstone 



| series). 



Lower Lias. 



( Rhsetic Marls (" White 

 \ Lias"). 



The plants of the Jurassic period consist principally of 

 Ferns, Cycads, and Conifers agreeing in this respect, there- 



