58 



(187G) in a field near the Rectory, the pits exposing 12 or 14 

 feet of finely bedded sand and gravel, the latter composed 

 chiefly of small rounded flint- and chalk-pebbles, with a few 

 rolled pieces of yellow quartz and brown quartzite, and many 

 broken fragments of Gryphcea dilatata. The total depth was 

 said to be about 20 feet ; the sands had a somewhat crag-like 

 appearance, but appeared to be quite unfossiliferous. North- 

 ward its edge or base is very little above the level of the 

 Fen. 



About Chatteris again its position is clearly defined, as it 

 here forms a low island or bank rising up from amidst the 

 surrounding fens, and the town is entirely situated on this 

 bank, which is here about three-quarters of a mile wide. Small 

 excavations in the Nursery gardens near the Station showed 

 4 or 5 feet of gravel similar to that at Somersham banked up 

 against a clayey loam ; I was informed that the whole deposit 

 was from 5 to 7 feet deep and rested irregularly upon stiff clay 

 with occasional "large oysters" in it, but could not ascertain 

 whether this was Boulder Clay or Oxford Clay. 



The clayey loam occurs in patches among the gravel, and is 

 left in working out the latter ; they evidently bear much 

 the same relations to one another as the loam and gravel at 

 Whittlesford. 



The gravel extends southward beyond the Mill Field and 

 northward beyond the Gas Works, near which place it is also 

 worked. I could discover no shells, but Mr Skertchly informs 

 me that Cyrena fluminalis has been found here together with 

 Cardium edide and Tellina solidida {balthica). 



Near Doddington the railway cuts through gravel, but the 

 pit near the Station at Wimblington is now grown over and 

 no longer worked; many shells (chiefly marine) used to be 

 obtained from this pit, which is probably that mentioned by Mr 

 Seeley as disclosing a floor of Oolitic rock pierced by Pholades. 



The gravel pit in the immediate vicinity of March Station is 

 likewise grown over, but gravel full of marine shells is seen in 

 the ditches leading into it. 



[The beds were well exposed in 1872, when part of the 

 section described by Prof Seeley in 186G still remained (see 

 ante, p. 18) ; the succession being as follows. 



