410 



SPECIAL GEOLOGY. 



of view, from its consisting largely of limestones adapted for 

 architectural purposes. It is subdivided into nine stages : the 

 subjoined table shows these subdivisions and their equiva- 

 lents, in England, Germany, and Trance : 



Lpper 



Conybeare. 



Portland Stone and Sand. 

 Kimmeridge Clay. 



nt-jji f Coral Rag. 

 Mlddle '{ Oxford Clay. 



Roemer. 

 Portland Kalk. 



Korallen Kalk. 

 Oxford Thon. 



Lower 



f Cornbrash, Forest Mar- "I 



ble,and Bradford Clay. J 

 Great Oolite and 1 



Stonesfield Slate. J 

 Fuller's Earth and f Walker Erde. 



Inferior Oolite. \ Unter Oolith. 



{Upper Lias. 

 Middle Lias. 

 Lower Lias. 



Possidonien schiefer. 

 Belemniten schichte. 

 Lias Sandstein. 



D'Orbigny. 



L'etage Portlandien. 

 Kimmeridgien. 



Corallien. 

 ., Oxfordien. 



Callovien. 

 Bathonien. 

 Bajocien. 



Toarcien. 



Liasien. 



Sinemurien. 



The following analytical table shows the different stages, 

 the lithological character, and principal localities of the 

 oolitic group.* 



Portland Stone 

 and Sand. 



Coarse oolitic shelly lime- 

 stone ; sometimes fine- 

 grained or compact, thick- 

 bedded, and with layers 

 of chert, and with subor- 

 dinate beds of sand. 



f Dark blue and greyish la- 

 Kimmeridge Clay. < minated clay, with gypsum 

 \_ and bituminous shale. 



f Coarse shelly limestones ; 



Upper Calcareous I more or less thick-bedded: 



Grit, Coral Rag, J coarse oolitic limestone, 



Lower Calcare- j sandy limestones abound- 



ous Grit. ing in corals, calcareo- 



1^ siliceous grits. 



Isle of Portland, Brill, 

 and Aylesbury, Bucks; 

 Thame, Oxon ; Tisbu- 

 ry,near Swindou, Wilts 



Kimmeridge, Dorset; near 

 Oxford ; Stone and 

 Hartwell, Bucks ; near 

 Swindon. 



Headington, Oxon ; West- 

 brook, Calne, and 

 Steeple Ashton, Wilts; 

 Mai ton and Scarboro', 

 Yorkshire. 



Tennant's British Fossils/ 



