INTKODUCTOEY NOTICE. 



THE history of that part of the earth's surface now occupied 

 by the Valley of the Thames, as treated in these pages, embraces 

 the whole period of geological time from the oldest rocks of 

 Malvern to the latest prehistoric alluvium. The mind perceives 

 and contemplates a long succession of lands and seas much different 

 from those we now behold, the beginning and ending of many 

 systems of associated life and varying physical agencies, all of 

 which have had a traceable influence on the present aspect of this 

 midland region of England. 



After marking the main features of physical geography, and 

 describing with the aid of maps and sections the systems of rocks 

 in the order of time, the organic remains of each great group 

 of strata are catalogued as fully as my own knowledge, combined 

 with the valuable aids which are in each case thankfully acknow- 

 ledged, has enabled me to accomplish the difficult task. 



These catalogues are illustrated by numerous engravings. 



The great series of reptilian bones, from the oolites, for which 

 the Oxford Museum has long been celebrated, has been examined 

 throughout, and the more remarkable genera have been made the 

 subject of special description and many drawings to scale. 



I could hardly have ventured on the great task of preparing 

 these descriptions without the advantage of being able to consult 

 at leisure the noble collection of Comparative Anatomy which some 

 years since grew to celebrity under the care of Dr. Acland in 

 Christ Church, and has since been greatly enriched in the 



