VOL. XVII. (3) SEVERN PLAIN IN GLACIAL EPOCH 367 



II. — The Superficial Deposits 

 The superficial deposits of that part of the Lower Severn 

 Plain which lies between the North and Mid-Cotteswolds on 

 the east and the Malverns and May Hill on the west consist 

 of :— 



(i) Debris from the various formations of the two Ranges 

 and from the intervening Triassic and Rhsetic 

 rocks. 



(2) Drift pebbles and boulders occurring mainly in the 



gravel terraces bordering the river Severn, and 

 pebbles scattered over the surface of the land to 

 some distance on either side, including most of the 

 low hills. The Drift pebbles consist of white 

 quartz, quartzites of various colours, the larger- 

 sized seldom exceeding 3x2 inches, lydian stone, 

 banded rhyohte of Uriconian type. Carboniferous 

 chert and limestone, and Cretaceous flints and 

 fossils. The boulders and pebbles of Scotch and 

 Lake District granites, Arenig felsites, and coarse 

 grits are well rounded. 



(3) Fine-grained quartzose sands without Drift pebbles, 



lying on the eastern side of the Plain, and generally 

 near to the Cotteswold escarpment. 

 • (4) Silts bordering the Severn and its tributaries. 



Debris from the eastern and western ranges of hills are 

 rarely seen on opposite sides of the Severn. The only recorded 

 instances of crossing from the eastern side are the single pebble 

 of the " King and Queen " rock of Bredon discovered by 

 Symonds at Holdfast, near Queenhill,' and the fragments of 

 OoUtic hmestone in gravel on the low ground to the north of 

 Highnam Church recorded by Lucy.'' On the eastern side of 

 the river I have observed rock fragments from the Malverns 

 only at Kempsey, Ripple, and Denmark Road, Gloucester. 



The river Severn or the high ground near to which it 

 flows has thus formed a marked hne of separation between 

 gravels derived from the rocks of the Cotteswolds and of the 

 Malverns. 



1 Severn Straits, p. 34. 



2 Proc. Cott. N.F.C., vol. v. p. 80. 



