250 LOWER OOLITIC HOCKS OF ENGLAND: 
limestones of the Great Oolite. These oolites are overlaid in 
places by the Bradford Clay, but on account of its inconstant 
character it is difficult to fix a definite plane of separation. These 
upper oolities will for convenience be referred to as the KEMBLE 
BEDS, as they are well shown near Kemble Station, the junction 
for Cirencester and Tetbury on the Great Western Kail way. 
North-east of Cirencester they appear to be overlapped by the 
Forest Marble. 
These difficulties in defining horizons are natural enough, and 
it is only needful to bear in mind that the subdivisions are made 
for local convenience. 
Organic Remains. 
Including the Stonesfield Slate, the Great Oolite has yielded a 
rich and varied fauna and flora. Especially noteworthy are the 
Mammalian and Oruithosaurian remains of the Stonesfield Slate ; 
but as a list of fossils from that deposit will be given further on, 
it will be sufficient here to notice the more generally distributed 
fossils of the Great Oolite. 
Among Saurians, the remains of Cetiosaurus, Megalosaurus, 
Steneosaurus, and Teleosaurus, are more commonly met with ; 
and of Fishes, those of Mesodon (Pycnodus}, and Strophodus. 
Of Cephalopoda, Belemnites are very rare, and Ammonites are 
only occasionally found ; the species A. subcontracts occurs also 
in the Fuller's Earth Rock. Other forms of Mollusca are abun- 
dant, together with Brachiopods, Polyzoa, Echinoderms, Corals, 
&c. The Corals are frequently calcitic, and they occur at various 
horizon?, more especially in the upper beds.* 
Excepting in the Stonesfield Slate, the Lower Division contains 
few, if any, distinctive fossils. The false-bedded oolites naturally do 
not preserve many species, though layers made up of comminuted 
shells of Ostrea, &c., and fragments of Echini and Crinoids occur. 
There are layers, however, which yield Gasteropods, and they 
may be obtained on the weathered surfaces of the stone. Even 
at the celebrated quarries of Minchinhampton, few fossils are to 
be obtained during a casual visit ; tho?e which were procured by 
Dr. Lycett, representing the labours of many years, Again at 
Ashford Bridge near Stonesfield, certain fossiliferous beds have 
been assigned to the " lower zone " of the Great Oolite ; but 
there seems no great reason for separating them from the " upper 
zone." 
In the Upper Division, there occur rich fossil-beds, sometimes 
made up of tine examples of Terebratula maxittata, or Ostrea 
Sowerbyi, and containing in abundance Lima cardiiformis^ Phola- 
domya Heraulti, Pecten vagans, Rhynchonella concinna, and 
Corals. Some of the rag-beds are largely made up of Polyzoa 
and minute Gasteropods. 
* See Tomes, Quart. Journ. Geol. Soc., rol. xli. p. 170. 
