282 Dr. FiTTON on the Strata below the Chalk. 



Ft. In. 

 [^Lo7ver Greensand.~\ 



1. a. Ochre and ferruginous matter 91 



b. Dark grey clay 4to0 9/ 



These substances, as at Great Hazeley &c., vary much in thickness, filling up 

 eroded cavities in the top of 2, next below, 



[PurbcchJ] 

 S. Rubble (the " Malm " of Garsington and Combe Wood) ; passing at the lower part into 

 firm, slaty, cream-coloured limestone, in which green matter is diffused, — but not in 

 grains; as in some of the upper Purbeck beds on the Dorsetshire coast. 



3. Clay: — uniform, without the stony fragments of the Portland "Dirt." I could not 



learn that any petrified wood had been found here in this situation. 



[Portland stone. '\ 



4. Stone, with Portland fossils, beneath which is sand here about 8 



[Portland sand.] 



5. Below the foregoing beds, on the descent towards Thame, are, — 



a. Sand, witli very numeroiis green particles, about 18 inches ; enveloping 



b. Rubbly, somewhat sandy, grey stone, with green particles, — like Kentish rag : 



} 



2 



coarsely concreted nodules, about 9 inches thick. 



iriicles, — like Kentish rag : -i 

 under which are knobby concretions, of a marly stone with green particles, >• 18 



) J 



containing clavellated Trigoniae 12 to 



G. Greenish grey sand. At its junction with 5, and for about 6 or 8 inches downwards, t 



are worn fragments of black flint; with Trigonia, Perna, and an oblong bivalve — a >• 30 

 Panopaea about J 



The whole thickness of the Portland-sand here is about 50 

 7. Beneath is clay. 



The greatest superficial extent of the Portland sand in this part of the country occurs near 

 the village of Thame ; extending from Scotsgrove and Scotsgrove Hill on the north, to Priest-end 

 and Morton on the south ; and from Dropshot, near Cotmore Walls, west of Thame, to the flat 

 between the river and Long Crendon. The apparent range of the formation thence, by North 

 Weston, Rycote, and Albury, to the heights above Wheatley, I did not examine. 



Pit at Barley Hill, east of Thame. 



The strata dip at an angle of about 5°, towards a point about 10° south of east. 



1. Soil and loam 2 ft. 6 in. to 2 ft. 9 in. 2 6 



[Portland Sand.'\ 



2. Irregular concretional lumps of calcareous stone with green particles, interspersed in i 



sand. Petrifactions numerous : — Pernae, with Lithodomi, and Ammonites ; Pla- I 6 



giostoma rusticu,n, (near Towersey) about J 



[This is evidently a continuation of the group at Long Crendon, on the opposite 

 side of the valley of the Thame. It precisely resembles part of the clifF immediately 

 north of La Creche, on the French coast near Boulogne.] 



3. Sand ; becoming greener as it descends. At the top, few concretions of stone. At i 



the bottom, the whole consists of greenish matter, not to be distinguished from that I 1 

 of the Lower green-sand near Folkstone. Serpulse very numerous J 



4. Coarse stone interspersed in sand ; with numerous fossils, especially Ammonites, and 1 



Trigonia gibbosa J 



5. More compact and uniform greenish or bluish rock, with green particles ; like soft 



Kentish rag 



na uniiorm greenisti or bluish rock, with green particles ; like soft 1 



In some of the quarries it is fit for building \ ^ 



