460 Notices of Memoirs — British Association — 



The new railway (Aj-nhoe and Ashendon) is cut along the divide 

 between the Cherwell and Ouse Kivers. The missing Sub-Bathonian 

 Series of the West lands were brought to view. Prominent there 

 were White Calciferous Limestones and Striped Marls and Lime- 

 stones. The author found the chalk-like limestone to be crowded 

 with the decayed heads of large crinoids of which it was made. 

 Above it passed into a blue crystalline limestone, here and there ; 

 a packed mass of the brachial joints of the crinoids. At the base of 

 all was the stratum of black vertical stripes (the striped beds), the 

 place of crinoid column and rootlets filled with carbonaceous granules 

 from dark beds above. The beds are now known to be marine, not 

 estuarine, as previously described. Sections of the chalk-like lime- 

 stone showed a pavement of discs of the crinoid {Apiocrhius) calyx. 



(8) On the STRtrCTURE OF THE LlAS IkONSTONE OF SoUTH WARWICK- 

 SHIRE AND Oxfordshire. By Edwin A. Walford, F.G.S. 



ri^HE ironstone of South Warwickshire and North Oxfordshire is got 

 JL wholly from the Middle Lias. The Northamptonshire ironstone 

 of the Inferior Oolite may be traced in the Burton Dassett Hills, 

 where it passes into a useless sandstone. 



Beds of the Middle Lias stone are seen in the quarries packed with 

 curved and interlacing stems something like masses of annelid tubes. 

 They lie upon the bedding plane. Other beds of the fine pentangular 

 and smaller ossicles of the Crinoidea range between. More rarely the 

 round columnar stems of forms like Apiocrinus are found. 



The author infers that the sea floor of the Middle Lias was a tangle 

 of crinoid growth, stage above stage. The Crinoid sea appears to 

 have spread through the Midlands into Yorkshire. Occasionally are 

 phases of invasion or dominance of shells of Brachiopoda. Beds of 

 Rhynchonella tetraJiedra and Terebratulce are interspersed in the 25 feet 

 of the ferro-crinoid rock-bed. 



The quarries and sections in the neighbourhood of Banbury show 

 the several phases described. 



In the Nodule Bed at the base of the Ironstone Series (zone of 

 Spirifer oxygona) crinoidal conditions appear in segments and stem 

 casts, mingled with large mollusca. Microscopic sections present 

 plates and segments of Crinoidea mingled with ferruginous Oolitic 

 grains of large size and fox-brown colour. 



The superimposed bed, the Best Rag, has in sections smaller 

 Oolitic grains of olive-green iron carbonate with ovoid calicular plates 

 of crinoids. 



The Top Rag, a grey-green compact stone, is a tangle of crinoidal 

 and other remains more or less broken and converted into Oolitic 

 iron granules. 



The Road Stone, the higher beds, shows its organic structure 

 mainly destroyed and converted into the ordinary red oxide. 



In 1896 I placed a short study on the making of the Middle Lias 

 Ironstone of the Midlands before the Iron and Steel Institute, which 

 appeared in their Proceedings. 



