61 



the annexed wood engraving is a reduced copy,) gives us the 

 relative position of these various beds, and the different quarries 

 in which they are exposed. I shall describe the beds in descend- 

 ing order, commencing with those exposed at the summit of 

 the hill. 



I divide the Inferior Oolite of our district into three zones: — 



1st, the Zone of Ammonites Farkinsoni. 

 2iicl, the Zone of Ammonites Humphriesianus. 

 3rcl, the Zone of Ammonites Murchisonoe. 



As these are all well developed in Cleeve HiU section, I purpose 

 prefacing the description of the beds belonging to the three 

 groups with a few general remarks on the typical character of 

 each zone. 



1. The Zone of Ammonites Farkinsoni. 



Synonyms. — Trigonia-grit and Gryphite-grit, Mtxrchison, 

 Geology of Cheltenham, 1845 ; Strickland, Quarterly Jom'nal 

 Geological Society, vol. vi., 1850. Ragstoue and Clypeus-grit, 

 Hull, Memoir of the Geological Survey, 1857. Zone of Anvmo- 

 nites Farkinsoni, Weight, Monograph of Oolitic Echinoderms, 

 1856. Spinosa- stage, Ltcett, Cotteswold HUls Handbook, 1858. 



Description. — The series of beds included in this zone exhibit 

 various degrees of development in Gloucestershire. In the 

 Northern Cotteswolds, where the best types are seen, the thin 

 beds of this stage rest on the Brachiopoda bed of the middle 

 division, as at Cleeve Hill; and when these are absent, on the 

 Upper Freestone, above the OoHte Marl, as at Leckhampton. 

 When the Upper Freestone is absent, as at Turkdean, they rest 

 on the Oolite Marl; at Sherborne, on the Lower Freestone; and 

 at Burford, on the Upper Lias. They are overlain by the Fullers- 

 earth, sometimes containing -shelly bands, with Ostrea acuminata. 



This zone is the most persistent of the three sub-divisions of 

 the Inferior OoHte, and is the only representative of that forma- 

 tion in the south-eastern parts of the County of Gloucester. 

 At Leckhampton Hill, the whole formation attains a thickness 

 of 264 feet, whilst at Burford, 20 miles to the eastward, it has 



