THE CORALLIAX ROCKS OF ENGLAND. 383 



of pisolite. These are followed by a thick false-bedded series 

 with few fossils, overlain by a rubbly bed with abundance of 

 rolled spines of Cidaris florigemma, associated with other fossils 

 which occur generally in lower beds than the Coral Rag proper. The 

 succeeding beds here are more calcareous than usual, and might 

 possibly be included with the limestones below as far as their fossils 

 are concerned ; but they are more gritty, and are followed by sands 

 and marls, with few fossils, and a ferruginous band corresponding 

 with the Sandsfoot grits or higher beds ; but these beds are local to 

 the neighbourhood of Sturminster. In the northern portion, the 

 Lower Calcareous Grit assumes more importance ; it forms exten- 

 sive banks near Cucklington, and may be traced downwards into 

 the Oxford Clay in Gillingham cutting. The succeeding beds are 

 almost entirely limestones of impure character, the upper portion 

 developing corals in some places, but not so many as to form a reef 

 or become conspicuous as a Hag. If any overlying beds were here 

 deposited, they have been washed off and their remains deposited on 

 the denuded limestones. There is more limestone in this region, in 

 proportion to the whole development, than in any other ; but it is 

 generally too impure to burn for lime. The limestones become pure 

 enough towards the extreme south-west, near Mappowder, where 

 there are several limekilns — as there are also in the neighbourhood of 

 Marnhull, where the false-bedded series is burnt. 



Wiltshire and Oxfordshire Range. — In this long belt are contained 

 several types, the most constant member being the Lower Calcareous 

 Grit, which consists of loose sands, sometimes of considerable thick- 

 ness, with occasional irregular bands of hard blue grit or huge dog- 

 gers. In the extreme south we have the interesting iron-ore of 

 Westbury (Section Y.) occupying an analogous position to that of 

 Abbotsbury, viz. the extreme top of the series. It has a bed of 

 glauconitic sand between it and the main limestones, which are of 

 minor importance here. Marls still intervene, as in the districts to 

 the south, between the limestone and the Lower Calcareous Grit. 



The section at Steeple Ashton is not very different from this, except 

 that the ironstone is unimportant, and a bank of corals is developed 

 at the top of the limestones, though of very limited extent. In 

 both these localities the total development is meagre ; and a little to 

 the north, at Seend, the whole is reduced to the Lower Calcareous 

 Grit, containing a rather peculiar fauna, and overlain directly by 

 the Kimmeridge Clay. 



In the neighbourhood of Calne (Section YI.) is a considerable de- 

 velopment of the Lower Calcareous Grit, which is fossiliferous at 

 Conygre, supports a coral reef without Cidaris florigemma at West- 

 brook, and thins out to very small dimensions northwards by Cat- 

 combe. \Ye have again a marly bed intervening between this and 

 the limestones, which in this area are of several inosculating types — 

 sometimes being a true Rag, full of corals, sometimes a set of false- 

 bedded limestones, and sometimes marls with interbedded occasional 

 limestone bands, as at Hillmarton. Yery slight traces of any beds 

 above these can here and there be noted, chiefly in the form of 



