TIIK T1IIASSIC SYSTKM 363 



unconformity, for there is no proof that this basement bed rests on 

 diifeivnt j'.-irt^ of the Bunter Series in different places. 



Tin- overlying sandstones are rather coarse grained and 

 invgularly bedded, generally of bright colours, red or yellow, but 

 sometimes pink or white. The current bedding is remarkable, and 

 tin- lamin.r often dip at high angles and change within short 

 distances. 5 The thickness is variable, but often about 200 feet, 

 and the group is persistent throughout Cheshire, Shropshire, 

 Staffordshire, and Worcestershire. To the south-east, however, it 

 thins out, and is absent in Warwick. 



Fossils have recently been found in the upper part of these beds 

 at Bromsgrove in Worcester ; they include both plants and animals. 

 The plants have been identified by Mr. Arber as Equisetites 

 "i-'iiaceus, Yuccites vosgesiana, and Voltzia heterophylla (twigs and 

 cones). The animals are Hyperodapedon Gordoni, a Labyrinthodont 

 (? Mastodonsaurus) ; the fish, Dipteronotus and Acrodus, Estheria 

 iii in nta, and fragments of Arthropods which are probably scorpions. 



The "Waterstones are brownish, even-bedded micaceous sand- 

 .-t"iifs and flagstones, with layers of red or green sandy shale; 

 they are therefore very different from the underlying beds upon 

 which they rest with a sharp line of demarcation. 7 Their surfaces 

 exhibit ripple-marks, sun-cracks, and they contain casts of salt- 

 Tvstals, all clear indications that they were deposited in shallow 

 water. Their average thickness is about 200 feet, but there is no 

 definite summit to the group as it passes up by intercalations of 

 shale and marl into the overlying Keuper marls. 



When traced south-east into Warwickshire, they overlap the 

 Lower sandstones and rest directly on the Carboniferous rocks. In 

 some places the waterstones have yielded bones and teeth of 

 Labi/rinthodon, Cladyodon, and Hyperodapedon, and also teeth of 

 tin- tish Dipteronotus cyphus, but these remains are rare. Reptilian 

 and Labyrinthodont footprints, however, are not uncommon. 



The Keuper Marls, though the thickest and most important 

 members of the series, are in some respects the least interesting, 

 because they consist of a monotonous succession of red clays (or 

 *' marls ") varied only by nodular layers and beds of gypsum and 

 occasionally beds of rock-salt, which are sometimes from 70 to 100 

 feet thick. 



The thickness of these saliferous marls in Cheshire is from 

 2000 to 3000 feet ; in Shropshire it is from 1500 to 1800, thinning 

 eastward to 800 and 700 in Staffordshire, and about 600 in 

 Warwickshire and Leicestershire In the last county they overlap 

 the sandstones and are banked against the Archaean rocks of 

 Charnwood Forest, partially filling the valleys between the hills. 



