THE CORALLIAN ROCKS OF ENGLAND. 315 



of some thickness on the top, the total seen being about 12 ft. The 

 fauna here too is much more scanty, and of a different character, the 

 most abundant fossils being the Echinoderms Echinobrissus scutatus 

 and Holectypus depressus, which are pretty numerous. The other 

 fossils noted were Littorina muricata (var.), Gervillia aviculoides, and 

 Opis Phillipsi. This, then, is not to be confounded with the former 

 quarry, but viewed as an example of what we have seen, and shall 

 see to occur often — an oolite underlying the Rag. The beds here 

 dip to the south, or in an opposite direction to those of the Rag- 

 pit; so that there is a synclinal, in which are found the Neoco- 

 mian sands. The presumed section of this reef is therefore as in 

 fig. 9. 



Fig. 9. — Presumed Section near Upware, Cambridgeshire. 

 (Length of Section about 1 mile.) 



South Phosphate North 



pit. diggings. pit. 



3 



1. Coralline Oolite. 2. Coral Rag. 3. ]S T eocomian. 



It is much to be regretted that more exposures are not to be 

 found here, as we have no indication of the Lower Calcareous Grit, 

 which probably exists. The plateau, however, is surrounded by 

 fen ; and it is, so to speak, quite a chance in the irregular pre-fen 

 denudation that has given us what we have, as it is possibly only a 

 fragment of a larger mass. 



V. The Yorkshire Basin. 



The Corallian beds of this area are completely cut off from all the 

 previously described ones by a long belt of country, extending 

 through the counties of Norfolk and Lincoln, where no such beds 

 are developed, but where the Kimmeridge gradually passes into the 

 Oxford Clay. The most southerly portion of the Yorkshire Coral- 

 lian area, under Acklam Wold, is distant 130 miles in a direction 

 N. by W. from the coral reef at Upware. The stratigraphical 

 features which in East Yorkshire characterize the whole of the 

 Jurassic deposits are seen in these beds, which, from whatever 

 cause, are grouped, like the rocks below them, in a basin round the 

 vale of Pickering. They have a development of great thickness and 

 variety, unequalled even by the thickest and most varied portion of 

 the Weymouth district. We do not forget that in this area the 

 original subdivisions were made out by Phillips, and that his iden- 

 tifications and figures of the fossils are amongst the most important 

 parts of our knowledge of the beds in England. Notwithstanding 

 this, the information conveyed, even by his last edition, is very 

 meagre, and leaves much to be desired ; nor do we know where 

 else to look for any additional details, except an occasional refer- 



