Vol, 68.] AEDEN SANDSTOI^E GROUP OF WAEWICKSHIHE. 2 §7 



Shelfield, Blackford Hill (near Henley-in-Arden), Mows Hill, and 

 near Wolverton. Plant-remains, nearly always badly preserved, 

 are to be obtained not only at Shrewley and Itowington, but at 

 TJmberslade, Mows Hill, south of Tanworth, and Shel field. Fish- 

 teeth and other fish-remains are somewhat similarly distributed, 

 but as a rule very sparingly. Mollusca, hitherto known only from 

 Shrewley, have lately been discovered by Mr. Wills at Shelfield, 

 6| miles to the south-west. Labyrinthodont and reptilian remains 

 and footprints have been rarely found away from Eowington and 

 Shrewley; but the above-mentioned facts go to show that the 

 zone may be searched almost anywhere for fossils with a reasonable 

 hope of success. 



The zone is typically from 20 to 25 feet thick, but occasionally 

 appears to reach 40 feet or even more. It thins rapidly eastwards 

 and south-eastwards to about 4 or 5 feet, and probably also north- 

 eastwards. In this easterly attenuation it follows the example 

 of the lower members of the Warwickshire Trias, which, with the 

 exception of the Lower Keuper Sandstone, disappear when followed 

 eastwards from the neighbourhood of the South Staffordshire coal- 

 field to that of the Warwickshire coalfield. 



The zone lies some 120 to 160 feet below the base of the Rhsetic, 

 the overlying marls being probably of somewhat variable thickness. 

 It is possible that in places it may be no more than 100 feet below 

 the Hhsetic deposits ; but a precise estimate is difficult, on account 

 of the slight undulations of the beds. 



YII. Correlation with other Areas, and Conditions op 

 Deposition. 



Prom the continuity of the Arden Sandstone over the area 

 described from Knowle and Barston to Alcester and Wixford, it 

 seems highly probable that Murchison & Strickland were correct 

 in asserting that the sandstone can be followed into Worcestershire 

 and Gloucestershire as a zone occurring always at the same 

 horizon. I am prepared to accept this view, although detailed 

 mapping will be required before the point can be regarded as defi- 

 nitely proved. The same lithological characters and the same 

 suite of fossils characterize the sandstone in those counties, as in 

 Warwickshire. Around the Hhaetic and Lower Liassic outlier of 

 Berrow Hill, near Tewkesbury, Mr. Linsdall Richardson ^ finds 

 that the Upper Keuper Sandstone is 215 feet below the base of 

 the Rhsetic, but its greater depth may be due to variation in the 

 thickness of the Upper Marls. 



The Upper Keuper Sandstone, near Leicester, a similar formation 

 with a similar fauna and flora, was stated by Mr. James Plant, in 

 1 856,^ to be 80 to 120 feet below the Lias, and it is, therefore, 



1 Q. J. G. S. vol. Ixi (1905) pp. 425-30. 



^ *0n the Upper Keuper Sandstone (included in the New Red Marls) & its 

 Possils at Leicester' Q. J.G. S. vol. xii (1856) p. 372. 



Q. J. G.S. No. 270. u 



