94 



INFERIOR OOLITE. 



Leckhampton Hill, near Cheltenham, exhibits one of the most typical sections in 

 Gloucestershire of the three sub-divisions of the Inferior Oolite, where the following beds 

 are admirably exposed: — No. 1, 2 and 3 represent the zone of Ammonites Parkinsoni : 

 No. 4 the zone of Ammonites Humphriesianus ; No. 5, 6, and a, b, c, the zone of 

 Amiiwnites Afurchisona ; these rest conformably on d, the Cephalopoda, or Jurensis bed, 

 which is here very thin; e, f, g, is the Upper Lias resting on h, the Marlstone. 



Section of Leckhampton Hill, near Clieltenham. 

 Fig. 31. 



Leckhampton Hill. 



6 



.. A, B, C. 

 - D. 



E, I, O. 



1. Trigonia bed. 



2. Gryphaja bed. 



3. Brown rul)bl.v Oolite. 



4. Flaggy freestone. 



5. Fimbria bed or Oolite marl. 



6. Freestone. 



A, B, c. Pea-grit and ferruginous Oolite. 



D. Cephalopoda or Jurensis zone. 

 E, F, G. Upper Lias sand and Upper Lias clay. 



H. Marlstone. 



I. Middle Lias clay-zone of Ammonites capri- 

 cornus. 



No. 1 . The U/jper Tri(jOida Ijcd is a coarse brown ragstone, containing many fossils, 

 chiefly as moulds and impressions of Trigonia costata. Sow., T. decorata, Lye, Lima 

 cardiiformis, Sow., HhynchoneJla concinna Terehratula spinosa, Schl., Sow., Ammonites 

 Parkinsoni, Sow., Echinohrissus clunicularis, Lhywdd, Ilolect^jjiis depresses, Leske, and 

 Clypcus Plotii, Klein ; in thickness it is about seven feet. 



No. 2. The Gryphma bed, an ancient oyster bank, almost entirely composed of 

 GryphdBa subloLata, Desh., with many other shells, as Pholadomya Heraulti, Ag., 

 Terehratula Meriani, 0pp., Tancredia donaciformis , Lye, Gervillia tortuosa, Phil., and 

 many other species ; the dominant shell is the GryphcBa ; this bed is about eight feet in 

 thickness. 



No. 3. The Lower Trigonia bed, a light-coloured, thin-bedded oolitic ragstone, con- 

 taining a large assemblage of Conchifera, which in general have their shells preserved, 

 with several species of Echinodermata and Corals. 



No. 4. Upper flaggy bastard-freestone, well seen above the Oolite-marl : twenty-six 



