THE ' DERIVED ' FOSSILS. 45 



There was no Oxford clay exposed within some few miles of 

 Upware, but yet the little Ammonites there are perfectly well 

 preserved. 



General. From the presence of these remanih materials of 

 Oxfordian to Neocomian ages inclusive and from the nature of the 

 rock, it is clear that the Upware and Brickhill deposits were formed 

 along the neighbourhood of a shore ^hose coast consisted of the 

 upper and middle Jurassic rocks. In pre-cretaceous times the 

 Kimmeridgian and probably the Portland ian rocks extended from 

 Dorsetshire to Yorkshire, and the Purbeck and Wealden conditions 

 also had a greater spread than now, probably reaching as far as 

 Potton if not to Upware. The old coast line ran from S.W. to N.E. 

 along a line to the west of Calne, Warminster, Farringdon, Oxford, 

 Potton and Cambridge to our present Wash, and thence trending 

 N.W. ran up into Yorkshire. 



The following lists include all the derived species known to 

 me from Upware and Brickhill. 



I. The 'Derived' Fossils of the Upware Deposit. 



JJelemniteS) Phragraicoe of Nerincea. 



„ abbreviatus, Miller. Aporrhais. 



„ explanatuSj Phill. Turritella or CJiemnitzia. 



Nautilus, sp. Exogyra (Coral Rag). 



Ammonites biplex, Shy. Gryphea dilatata, Sby. var. Coral 



„ cordatuSj var. Marice, Rag, &c. 



d'Orb. Ostrea gregaria, Sby., Coral Rag. 



Ammonites biplex, d'Orb., of the Lithodomus inclusuSy Pliill., Coral 



Oxford clay. Rag. 



Ammonites Deshayesii, Leym. Modiola, sp. 



„ small smooth species Perria Midletti (in dark grit). 



(] Neocomian). „ Ricordiana, d'Orb. 



Ammonites Koenigi, Sby. (collection Pecten vimineus, Sby., Coml Rag. 



J. F. Walker, M.A.). Unicardium, Coral Rag. 



Ancyloceras, sp. (J. F. W.). Opis Corallina, Coral Rag. 



,, sp. in gritty phosphate. Fectunculus, ribbed species, in 



Hamites. phosphate. 



Chemnitzia Ueddingtonensis, Sby. Trigonia iiicurva, Sby. ? 



Cerithium muricatum,, Sby. ,, gibbosa, Sby. ? 



Litorina (in dark grit). Cardium striatulumy Sby. 



Cerithium (ditto). „ dissimile, Sby. 



Fleurotomaria reticulata, Sby. Lucina Portlandica, Sby. 



,, sp. Cyprina, large species. 



1 Buccinum naticoides, Sby. Myacites, of Portland oolite, and 



Natica, 2 sp. Kimmeridge clay. 



