OF XORTH OXFORDSHIRE AND THE CLTPETJS-GRTT. 231 



list. The common forms are Astarte minima, Pecten lens, and Lucina 

 despecta, with which occurs more rarely Rliynclionella spAnosa. A 

 fragment of Ammonites ParJcinsoni came apparently from this 

 stratum also. The Trigonice, though not numerous individually, 

 array themselves in great force specifically ; noticeable amongst 

 them are the bold and beautiful valves of T. producta, T. gemmata, 

 and the varieties of T. signata. Several of the species named evidence 

 a horizon of the Inferior Oolite approaching that of the Trigonia- 

 grit ; Astarte minima and Trigonia signata occur in the Grey Lime- 

 stone of Scarborough ; but T. producta seems not to have ranged 

 lower than the Trigonia-grit of Cheltenham and Stroud. 



The plant-bed of series D suggests a change of conditions from 

 the decidedly marine and coralline phase of the lower beds. Car- 

 bonaceous fragments occur more or less throughout the whole of 

 this series, especially in the limestones Nos. 14 and 19 ; the fauna, 

 however, is still marine. Quenstedtia ohlita, again, a species of the 

 higher beds of the Cotteswolds and Yorkshire, occurs in series D, 

 associated with the remains of stems of reed-like plants and Avood. 



The series E, of sandy limestones passing at times into a bastard 

 freestone, which we have not met with before reaching the Hook- 

 Norton area, covers the greater part of the high lands about Hollright, 

 Long Compton, and Addlestrop. It is capped here and there by 

 coarse oolitic grits hereafter to be described. I have measured 

 sections near Chipping Norton attaining a thickness of 20 feet. 

 Towards the base of this series occurs a sandy limestone crowded 

 with an oyster approaching the Ostrea calceola of Quenstedt {pyoci- 

 formis of Wright), together with numerous specimens of Lima cardii- 

 fonnis. 



Table B (pp. 239-242) gives a list of the Hook-Norton fossils. 



Between Hook Norton and Swerford, about a quarter of a mile from 

 the latter village, Mr. Bennett's quarry shows a series of the upper 

 beds of the Inferior Oolite which exhibit the passage-beds into the 

 Great Oolite more clearly. It is as follows : — 



ft. in. 



1. Humus 1 6 



2. Grey clay with white concretions 6 in. to 2 



3. Black clay mingled with fragments of marly limestone, containing 



Kilvertia, Cerithwm, and Lucina, resting unconformably on No. 4 7 



4. Grey siliceous crystalline limestone with traces of Nerincea and 



bivalves 11 



5. Brown clay 1 



6. Black sand 3 



7. Flaggy fawn-coloured sandy limestones and sand 4 2 



8. Compact light fawn-coloured limestone, base not shown 6 



The pit furnishes the road-metal for the greater part of Swer- 

 ford parish, and is worked close to the edge of a fault which traverses 

 the country from E. to W. The fragments of grey limestone min- 

 gled with the black clay are identical with similar fragments from 

 the top of the Hook-Norton cutting. Out of a fissure towards the 

 lower end of the pit have been extracted some great blocks of 

 travertine-like stone with beautiful surfaces made up of radiating 



