FOSSIL MOLLUSC A. 263 



Wotton, Sevenoaks, Nutfield, Pulborough, and Peters- 

 field. Near Folkestone there occur layers of a 

 siliceous limestone often full of Ostrea, Area, Lima, 

 Exogyra, Panopcea, and Pecten. 



At Shotover Hill, near Oxford, there are strata 

 of this age which contain Unio, Cyrena, Paludina, 

 and other fresh-water forms. In Bedfordshire (as, 

 for instance, at Patton, Woburn, Ampthill, Sandy, 

 Wicken, and Upware) the sands are worked in order 

 to get at a " coprolite " bed, which is frequently as 

 much as two feet thick. These " coprolite " workings 



Fig. 242. Inoceramus sulcatus (Gault). 



are capital places for fossils, all phosphatized, or 

 converted into phosphate of lime, and most of them 

 of considerable interest and importance, because they 

 have been "derived" or washed out of the older 

 formations where they were originally deposited, such 

 as the various strata of the Oolite and Wealden. 

 Ostrea, Gervillea, Exogyra, Gryphcea, etc., are very 

 common. 



The fossils of the Gault have always been admired 

 on account of their great beauty ; many of them still 



