100 
PROCEEDINGS COTTESWOLD CLUB 
1919 
Moreover the geological events in this district, of which the 
greater part if not the whole is unglaciated, and much is devoid 
of Drift, are more difficult to elucidate than in regions where 
the passage of each of the ice-sheets has left its characteristic 
marks of glaciation. Correlation with the Pleistocene deposits 
of other areas is also rendered difficult by the absence of human 
remains of Glacial age. 
Continued observation of fresh sections shoving changes in 
the constituents and modes of deposit, and the reference to 
their source of many at one time doubtful Drift specimens, have 
allowed a more complete classification to be made. The results 
are now presented as a supplement to previous communications, 
and as a summary of conclusions from the whole of the available 
evidence. To render the following pages serviceable to 
members who wish to gain only a general idea of the subject 
some repetition of parts of my former papers and references to 
contributions by other writers will be necessary. For the 
convenience of future workers in this field of research those 
papers will be bound in one volume and placed in che Library 
of the Club. 
A Bibliography numbered to correspond with the references 
in the text and a sketch map of the region are appended. The 
rivers and places on the map are referred to in this and 
previous papers. 
For assistance in the identification of some of the Drift 
specimens I am indebted to Dr. Sir J. J. Harris Teall and 
Dr. Aubrey Strahan, the late and present Directors, and Dr. 
H. H. Thomas, the Petrographer, of the Geological Survey, 
whose kind services have been of great value. 
The following are the principal varieties of rocks in the 
superficial deposits under review : — 
Class 
A. — Gravels, sands and clays, composed of the disintegrated 
portions of the rocks upon or near winch they lie. 
B. — Cretaceous materials consisting mainly of black flints and 
blocks of chalk, probably derived from strata formerly 
extending over the district. 
