A. E. Trueman — Fauna of Hydraulic Limestone. 151 



Yellow calcareous clay 

 Pale flaggy limestone 



(Skerries) 

 Coarse clay 



Yellow earthy nodular lime- 

 stone with ' spine-bed ' 

 at top 



Dark calcareous shale 



Blue-hearted earthy lime- 

 stone 



Shale . 



in. 





 10 



r Dark, blue-hearted \ 

 limestone 

 Shale 



£ 

 o 



ffl 



(Twins) 



Limestone as above-' 



Shale .... 



Blue, wavy -banded, fine- 

 grained limestones, with 

 shell bands near top 



Fine-grained, well -lami- 

 nated, blue calcareous 

 mudstones 



Fine dark-blue limestone . 



Mudstones, as above . 



Variable limestone bands . 

 \ Mudstones, as above 



1 3 



Worn Saurian vertebras, Lima. 

 Psiloceras planorbis, Anim. Johnstoni. 



Echinoid spines, Ostracods, fish- 

 scales, Lima, Belemnites. 



Ps. planorbis, Ostrea, Lima, Modiola 

 minima, Turbo sp. 



Spines, Fish-teeth, Foraminifera. 

 Ps. planorbis, M. minima. 



Spines, Ostracods, fish-teeth, 



Foraminifera. 

 Pecten sp., Lima, M. minima,. 



Spines, Ostracods, many Foraminifera 



(Nodosaria). 

 M. minima. 



Foraminifera, spines, Ostracods. 

 Ostrea irregularis, O. liassica, 



Pleuromya crowcombei, Avicula 



cygnipes, M. minima, spines. 

 M. minima and Ostracods, rare ; 



worm bores. 



M. minima, rare. 

 Ostracods, rare. 

 Ostrea, rare ; M. minima. 

 M. minima. 



Soft blue clay, Bksetic, below level of working. 



Similar beds without Planorbis are described as " pre- Planorbis 

 beds " by L. Richardson in the neighbourhood of Cheltenham. 1 



A comparison of the above section with that at Barrow-upon-Soar 

 (in North Leicestershire, 11 miles distant) is instructive. While in. 

 the section just described about 8 feet of beds occur between the Upper 

 Rhsetic and the lowest beds with the zone fossil, there Psil. planorbis 

 occurs also in beds which immediately succeed the Upper Rhsetic. 



As shown by the following table, the beds without Planorbis at 

 Owthorpe (and also at the other exposures mentioned previously) are 

 of Liassic age, for the fauna differs only slightly from that of the 

 overlvinq; beds with Planorbis. 



Upper Rhsetic. 



Ostrea liassica . 

 O. irregularis . 

 Lima gigantea 

 Saurian remains 

 Pecten sp. 

 Foraminifera . 

 Echinoid spines 

 Pleuromya crowcombei 

 Avicula cygnipes 

 Estheria minuta 

 Modiola minima 

 Cytheridea sp. 



C. 

 C. 



r. rare; c. fairly common ; C. very common. 

 Geology of Cheltenham, pp. 21-36. 

 Geology of Melton Mowbray and South-East Notts, p. 29. 



