he has taken in helping me 

 to identify the cephalopoda 

 which I had collected ; while 

 for assistance in identifying 

 other fossils I have to thank 

 Prof. H. G. Seeley, Mr. E. T. 

 Newton, Mr. H. A. Allen, 

 and Dr. F. L. Kitchin. I also 

 owe some valuable sugges- 

 tions to Dr. C. G. Cullis. 



II. The Bid's-Hill Section. 



Kids Hill is the name given 

 on the Ordnance-map to a 

 small hill set upon the north- 

 eastern spur of Brill Hill, its 

 summit marked by a little 

 plantation of firs. Two little 

 brooks, each arising from one 

 of the numerous springs at 

 the base of the Portland 

 Sands on Brill Hill, flow 

 north and south of Bid's Hill, 

 on their way to the Bay and 

 the Thame respectively; and 

 so this hill forms part of one 

 of the secondary lines of 

 watershed within the Thames 

 Basin. Along the valley of 

 the northern stream for some 

 little distance the road from 

 Wotton to Brill and the so- 

 called ' Oxford & Aylesbury 

 Tramway' run side by side, 

 and here, at the northern 

 foot of Bid's Hill, are the 

 brickfields of the Brill Brick 

 & Tile Company. 



The general geological 

 structure of the hill is shown 

 in fig. 1. In the preparation 

 of this section, the ground 

 was first measured up by 

 means of a reflecting level, 

 along a line as near the 

 western edge of the brick- 

 field as possible, distances 

 being measured by paoing. 

 The measurements having 

 been checked by reference to 



points actually marked either 

 1 



2507 



