18 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Apr. 6, 



the Cephalopoda-bed of Haresfield Hill. On this subject he ob- 

 served — " A few miles to the south the Pisolite disappears, and is 

 replaced near Painswiek and at Haresfield Hill by strata containing 

 ferruginous oolite-grains in a brown paste. This is the precise 

 equivalent of the well-known oolite of Dundry, near Bristol, which 

 maybe recognized as far as Bridport, on the Dorset coast*." A 

 comparison, however, of the species of Ammonites and other shells 

 collected in these different localities shows that, besides a similarity 

 in lithological structure, there is nothing in common between the 

 strata. 



The position of the Ammonite-bed at Dundry Hill has likewise 

 been a source of error, placed, as it is, so near to the Upper Lias 

 sands, and overlain by other shelly beds and thick-bedded oolitic 

 limestones, just as the Cephalopoda-bed at Procester Hill and 

 Haresfield Hill is overlain by the shelly beds and oolitic limestones 

 of the zone of Ammonites Murchisonce. The fact, however, appears 

 to have been overlooked, that the Oolitic beds in the South of Eng- 

 land vary much in thickness in different localities, and even thin 

 out within short distances from each other. "When this happens, 

 strata which in one locality are separated by a considerable thick- 

 ness of rock, in others are brought into juxtaposition. The thin- 

 ning out of the zone of Ammonites Murchisonce and the absence of 

 the zone of Ammonites Humphriesianus, near Burford and other 

 localities in the north-east parts of the Northleach district, have 

 brought the zone of Ammonites ParTcinsoni in close relation with 

 the clays of the Upper Lias ; so, in like manner, the thinning out of 

 the zone of Ammonites Murchisonce at Dundry Hill has brought the 

 zone of Ammonites Humphriesianus in close relation with the sands 

 of the Upper Lias. 



In the Northern Cotteswolds the zone of Ammonites Humphriesi- 

 anus is best represented by a series of ferruginous oolitic limestones, 

 raised for road-material at Cleeve Hill, between Cheltenham and 

 "Winchcomb, and which are well exposed in the following section. 



A. Section VII. — The Rolling-bane Quarry ; Cleeve Hill, 

 North End. 



On leaving the "Winchcomb road, about a quarter of a mile beyond 

 the " Rising Sun," by the new stables, and ascending the escarp- 

 ment at this point, the Pea-grit is seen in position near the wall, 

 containing Terebratula simplex, Pygaster semisulcatus, numerous 

 fragments of Pentacrinites, and other fossils of this rock. A few 

 yards above, the freestone (much displaced) crops out southward ; 

 and still higher up the hill we enter the quarry called by the 

 workmen the " Rolling-bank." In the 44th sheet of the Geological 

 Survey Maps, this escarpment is marked " Tumbled Oolite and 

 Under-cliffs," — names which signify the disturbed condition of some 

 of the beds, produced probably by a slip of the Oolitic strata over the 

 unctuous clay of the Upper Lias. 



* Quart. Journ. Geol. Soc. vol. vi. p. 250 (1850). 



