Vol. 68.'] PALJEOXTOLOGY OF THE WARWICKSHIRE COALFIELD. 609 



stones of AUesley (a portion of which is in the Sedgwick Museum, 

 Cambridge) show that it possesses uniseriate bordered pits. The 

 plant cannot therefore be referred, either to the Equisetales, or to 

 the Lj^copodiales ; it appears to be coniferous wood of Cordaitean 

 affinities. Fragments of such woods are common in the drift- 

 gravels of the neighbourhood. 



There remains the conifer Walcliia imhricata, the only plant 

 in the list that is of stratigraphical value. The genus Walcliia 

 is known from the Stephanian beds of the Continent — a series 

 which is not known to occur in Britain. It has also been recorded 

 from the Upper Coal Measures (Keele Beds) of both the North and 

 the South Staffordshire Coalfields, in which it is exceedingly rare. 

 Walchia is, however, a typical Permian plant, and it is only in 

 beds of Permian age that it becomes common. The abundance 

 of the plant in the Kenilworth Sandstones at this locality suggests 

 that the rocks in question are Permian. 



Until definite palaeontological evidence to the contrary is forth- 

 coming, the Corley Conglomerates and the Kenilworth Sandstones 

 must be both regarded as of Permian age. 



(C) The Base of the Trias. 



The Trias of Warwickshire is not fully developed, two of the 

 subdivisions being absent ; a third is very thin, while a fourth dies 

 out south-eastwards within the limits of the district. The follow- 

 ing subdivisions are represented : — 



IT . / Upper Keuper Marls. 



^^1 ^^ \ Lower Keuper Sandstone. 



Banter Banter Pebble-Beds. 



The relationship of the Trias to the older rocks is a matter of 

 some importance, to which a brief reference will now be made. 

 The accompanying map (PI. LXI) shows clearly that the Trias 

 is everywhere unconformable to the older rocks, and that its 

 outcrop successively overlaps the Cambrian, the Carboniferous, and 

 the Permian. In the north near Polesworth (where the Bunter 

 is the lowest member of the Trias), east of the boundary-fault of 

 the coalfield, a small area of Permian with Corley Conglomerate 

 at the base is seen dipping east-north-eastwards at 30° under 

 Bunter Pebble Beds which dip south-eastwards at 25°. The Pebble- 

 Beds in turn dip beneath the Lower Keuper Sandstone, and the 

 latter beneath the Upper Keuper Marls. The Bunter, which is 

 well exposed in several quarries near Hoo Hill, is only about 

 250 feet thick. Farther south, near Atherstone and in Morevalo 

 Park, the Bunter is absent, so that the Lower Keuper becomes the 

 basal member of the Trias. It is noteworthy that here, as at other 



Q. J.G. S. No. 272, 2x 



