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PROCEEDINGS OP THE GEOLOGICAL SOCIETY. 



[Mar. 6, 



planes are generally a little apart, and often coated with red, green, 

 or purple clays or marls ; bands of marls similarly coloured are occa- 

 sionally met with among the limestones (Hexthorpe). 



Fig. 1. — Sketch-section of the Succession of the Permian Strata in 

 South Yorkshire. 



Coal - New Red 



measures. Sandstone. 



& c d e f 



f. Bunter Schiefer. e. Brotherton Beds. d. Lower Bed Marl and Gypsum. 

 c. Small-grained Dolomite. b. Lower Limestone. 



a. Bothliegendes or Lower Bed Sandstone. 



In certain localities some of the beds contain casts of Axinus 

 dubius and Myalina Hausmanni, together with some obscure remains 

 that seem referable to Algce. 



The Lower Bed Marl and Gypsum immediately underlie the pre- 

 ceding beds. They consist of beds of red and variously coloured 

 marls with bands of gypsum, are apparently unfossiliferous, and 

 are rarely seen in section. 



The slight importance which the Lower Eed Marl seems to hold 

 in the physical geology of this district, the absence of any palseon- 

 tological feature belonging to it, and the occasional presence of red 

 and other coloured marls in the Brotherton Beds have induced me to 

 describe it along with the last-named deposit, and to suggest the 

 propriety of considering it as part of the same subdivision. I do 

 this with much diffidence and some doubt, being aware that such a 

 view is opposed to the opinions of Prof. Sedgwick and the officers of 

 the Geological Survey. 



The Brotherton Beds are well exposed at Knottingley, Womersley, 

 Hexthorpe, Wadworth, and many other localities, being much worked 

 for lime -burning and road-repairs. 



3. Small-grained Dolomite. — A crystalline, subcrystalline, or 

 compact limestone of a slightly yellow, cream-coloured, whitish or 

 lustrous grey tint. Thickness of beds ranging from 3 feet to 

 1 foot and under. Stratification very irregidar, beds thickening to 

 maximum, and thinning out suddenly ; it being almost the excep- 

 tion for one stratum to appear in section for a moderate distance : 

 planes of stratification curiously pitted. Among the uppermost beds 

 occur intercalations of greenish clay or marl a few inches thick (Cliff 

 Quarry, Brodsworth). 



This limestone seems to be entirely void of fossils, except inferiorly 

 towards its junction with the Lower Limestone, where faint traces of 

 them occur (Town Quarry, Conisborough) ; and in these lowest beds 

 there is also a tendency towards an oolitic character, that is never 

 to be observed in the middle and upper parts, though much less 

 evident than in some of the beds of the Lower Limestone. 



The very peculiar stratification of the Small-grained Dolomite is 



