GEOLOGY 



flints, and was apparently derived from the north-east and east. The 

 third or local drift lies at the foot of some of the Oolitic hills and 

 appears to be made of exclusively local materials. Lastly comes the 

 jiuviatile type, a mixture of the other three ; it occurs in patches along 

 the Avon valley and is traceable from Lawford to Defford at heights 

 ranging up to 40 feet above the river, and is the only drift containing 

 organic remains of contemporaneous origin ; from it have been obtained 

 shells of mollusca and bones of mammalia at various places, including 

 Lawford and Shottery, at the latter of which were found teeth of 

 elephants. 



Brodie's papers added much to our knowledge, and he has recorded 

 details 1 of an extensive deposit of drift over the tableland lying to 

 the north-west of Warwick and extending thence in the direction of 

 Birmingham. Occasional large rounded boulders of sandstone occur, 

 but generally the pebbles are small and consist of sandstone and quartz. 

 Flints are present, especially at Hazeley and Hatton, ' where masses of 

 large unrolled flints occur, looking as fresh as if they had lately come 

 from a chalkpit.' At Rowington the soil of a small field contained 

 little bits of very hard chalk rounded and scratched, and there were 

 present also flints, pieces of greensand, and fragments of various Jurassic 

 rocks, together with Carboniferous sandstone with plant remains, and 

 several boulders of igneous rocks such as granite and syenite. The Lias 

 outlier of Brown's Wood, south-west of Henley-in-Arden (see p. 18), 

 is covered with drift derived from districts lying to the north. At the 

 same time Brodie pointed out that fossils similar to those then recently 

 found in the Lower Silurian pebbles of the Trias of Budleigh Salterton 

 in Devonshire are to be found in some of the quartzose pebbles of the 

 Warwickshire drift, and this observation has since been confirmed by 

 Mr. W. J. Harrison. 2 



Mr. T. G. B. Lloyd 3 in 1870 recorded certain observations on the 

 drift of the Avon valley and pointed out the occurrence on the higher 

 ground of a bed of chalky boulder clay, a stiff" compact mass of sandy 

 unstratified clay or earth, from slaty-blue to purple in colour, full of 

 grooved and striated pieces of Lias limestone, white chalk, quartzite 

 pebbles, flints and syenite boulders. This seems to be specially preva- 

 lent over the outcrop of the Lias, changing its colour to red where it 

 overlies the Trias. Associated with this typical boulder clay are irregu- 

 lar and impersistent beds of sand and gravel. On the lower grounds 

 are beds of quartzose flinty gravel and local drift containing shells and 

 bones of mammals. Chalky boulder clay to a depth of 30 feet has 

 been described by Mr. W. Andrews 4 as occurring in a railway cutting 

 at Berkswell. 



The deposits of the neighbourhood of Rugby have been described 

 by Mr. J. M. Wilson & under two heads high level deposits and valley 



1 Brodie, Quart. Journ. Geol. See. xxiii. (1867), 208. 



8 Proc. Birm. Phil. Soc. (1882), p. 157. 3 Quart. Journ. Geol. Soc. xxvi. (1870), 202. 



* Proc. Warw. Field Club, 1884. Quart. Journ. Geol. Soc. xxvi. (1870), 192. 



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