706 MESSRS. S. S. BTJCKMAN AND E. WILSON [Nov. 1 896, 



eastern portion o£ the hill, that part which lies east of the Chew 

 Stoke Road. 



The general characters of the rock may be stated as follows : — 

 Coarse, yellowish-brown, ironshot oolite — the oolitic feature almost 

 universally present, but most strongly developed in the upper 

 portion of the rock, — distinguished by the presence of the species 

 noted in our faunal lists. 



It was probably the iron shot-oolitic character which deceived the 

 officers of the Geological Survey, as it has doubtless misled geologists 

 subsequently ; but the fossil evidence is clear, moreover it is fairly 

 abundant, and so too are the exposures about the eastern part of 

 the hill. Yet, as a matter of fact, round the greater part of the hill 

 the boundary-line of the Inferior Oolite on the Survey map is 

 carried well below the outcrop of the Marlstone — just as far below, 

 in fact, as would have been correct had the Marlstone been actually 

 ' the Ironshot Oolite ' of the Sauzei hemera. 



(2) The Blue Ironshot-beds. 



In order to be precise we have called the hard deposits lying upon 

 the Marlstone, or separating the upper and lower clays where the 

 Marlstone is absent, ' the Blue Ironshot-beds,' from the noticeable 

 characters of the matrix ; but colloquially we have spoken of them 

 at times as ' the Cephalopod-bed,' because in part these deposits are 

 contemporaneous with part of the Cotteswold Cephalopod-bed, at 

 other times as ' the bifrons-be&s,' because of the presence of Hildo- 

 ceras bifrons. 



The series of deposits forming the so-called ' Blue Ironshot-beds ' 

 were exposed by excavations at the western end of the hill and at 

 Maes Knoll ; and at many other places on the flank of the hill these 

 deposits have been found, recognizable by their peculiar matrix 

 and the contained fossils. At the western end the strata are very 

 thin, but nevertheless furnish evidence of deposits laid down during 

 the following henierge: falciferi, bifrontis, striatuli,fallaciosi — so that 

 there is wanting any deposit made during the variabilis hemera. 



At Maes Knoll the beds are thicker ; but it is evident that the 

 deposit is of a fairly uniform and persistent thickness throughout 

 the range of the hill. At the latter place a very good section was 

 obtained by excavation, showing a clear sequence of deposits during 

 the hemerse noted above and during that of variabilis as well ; in fact 

 the deposit of this latter hemera is very distinctly marked by fossils. 

 As to the other beds, perhaps it would be more correct to say that 

 the deposit laid down during the bifrontis hemera is not present 

 at Maes Knoll, but that it has been removed and redeposited during 

 the variabilis hemera. 



As to the correspondence of this bed or series of beds with those 

 of the Cotteswolds, it may be seen in Table VI., facing p. 704 ; but 

 we may note that the deposit separating the beds of the falciferi 

 and striatuli hemerse at Maes Knoll is only 18 inches in thickness, 



