1852.] 



BROWN — UPPER TERTIARIES AT COPFORD. 



187 



ern part of this excavation (which is somewhat basin-shaped), the 

 yellow clay laminae vary in their dip from S. to S.E. and to nearly E. 

 This laminated yellow and blue clay is, in my opinion, the same as 

 the blue clay of the eastern and western sections, which latter is co- 

 extensive with the other beds, hereafter mentioned, that occupy the 

 site of what appears to have been an ancient freshwater lake, being 

 more than a mile in extent from east to west, and about three- 

 quarters of a mile in a north and south direction. 



The clay undergoes a process of puddling and washing in a horse- 

 mill preparatory to its being used in brick-making ; and from the 

 debris of these washings various organic remains and rock-fragments 

 have been obtained : — rolled fragments of chalk, rolled and angular 

 flints, fragments of Kimmeridge clay, and minute fossils from the 

 upper secondary rocks. 



I have formerly noticed the occurrence of fragments of freshwater 

 shells in the upper part of the blue clay (No. 4 of the Section), 

 especially Valval a and opercula of Bithinia ; and on a recent re- 

 Fig. 2. — Metacarpal of large Bear, from Copford. 



a. Upper surface. 



b. Proximal articular surface. 



c. Lateral view. 



