A HISTORY OF DEVONSHIRE 



Recent 



Pleistocene 



Terti 



ary 



Alluvium and stream gravels. Peat or peaty soil 

 Sand and shingle beaches. Blow^n sand 



Bagshot , 



Residue of pre-existent Cre- 

 taceous and Tertiary rocks 



Submerged forests 



Head or stony loam exposed on the coasts, white 

 clays w^ith Betula nana in the Bovey valley 



Raised beaches ; old river gravels contempo- 

 raneous with raised beaches and marking prior 

 and subsequent stages in the excavation of the 

 present valley system 



Cavern deposits ranging from recent to (?) early 

 Pleistocene 



Clays with lignite bands, sands and gravels of 

 the Bovey valley and of Petrockstow 



Gravels at higher levels. Gravels on the Cre- 

 taceous tableland 



Clay with flints and chert 



Chalk 



Cretaceous 



Liassic 



Rhsetic 



New Red 



Sandstone 



Series 



o 

 "5; 



' Sands, etc., represent- 

 ing Upper Greensand, 

 Malmstone, and Gault 

 Clay 



Lower Lias 



White Lias 

 Black Shales 



Keuper . 



Upper 

 New Red 



Lower Keuper or 

 Bunter 



Middle \^ ^ _ . 

 NewRedP""*"*"'^"'"'^" 



Upper Chalk. Chalk with many flints on hard 

 nodular chalk, zones of Micrasters and Holaster 

 planus 



Middle Chalk (Turonian). Chalk with layers of 

 flint (zone of Terebratulina). Hard chalk, in- 

 cluding Beerstone (zone of Rhynchonella cuv'ieri) 



Lower Chalk (Cenomanian). Quartziferous 

 limestone and calcareous sandstone (chalk 

 present at Membury) 



Chert beds on sands with shell bands and layers 

 of sandstone with concretions, used for whet- 

 stones in parts of the Blackdowns, on nearly 

 unfossiliferous sands 



Sands with beds of clay in tunnel near Honiton 

 and at WhiteclifF and Branscombe on the coast 



Beds of limestone and dark shale. In the lower 

 part (zone of Ammonites planorbis) limestone 

 beds predominate 



White or cream-coloured limestones and marly 



beds 

 With Avicula contorta — and a bone bed — on grey 



and greenish marls 



Red and greenish cuboidal marls with veins of 

 gypsum, with sandy and calcareous layers, in 

 lower part more or less silty 



Red sandstones, in parts with calcareous concre- 

 tions and two or three bands of a concretionary 

 brecciated character ; occasional pebbles, and 

 false-bedding in lower part 



Pebble beds with foreign pebbles gradually giving 

 place to rocks of local derivation, northward 



Red marls (cuboidal) without gypsum 



Red marls with thick even beds of red and 

 whitish sandstone, developed at Straight Point, 

 where they contain local calcareous concre- 

 tionary beds and brecciated bands 



10 



