236 E. A. WALFOED ON THE " NOETHAMPTON SAND " 



clays, it would be difficult to imagine them to have been formed sub- 

 sequently to the deposition of the impervious layers. 



About half a mile south of Langton Bridge, at the Cross Roads, the 

 Clypeus-grit, with its characteristic fossils, G. Plottii, Terebratula 

 globata, &c, may be noted in the road-cutting. Its junction with the 

 Upper Lias is apparent by the growth of coarser grass and rushes. 

 The walls by the roadside are built of the ragstone abounding in the 

 fossils mentioned. Resting upon the grit may be seen a few feet 

 of sandy limestones of the lower Hook-Norton type, the probable 

 equivalents of C and D. In stacks of stone by the roadside, derived 

 from the banks, I have noted the following fossils : — Pecten articu- 

 latus, Trigonia jproducta, Astarte minima, Myacites Goldfussi, Perna 

 mytiloides, and plant-remains. These pass into sandy limestones, 

 with abundant carbonaceous fragments, containing Trigonia signata, 

 which in turn are covered by the siliceous oolites of which sections 

 may be seen near. To Mr. Windoes, of Chipping Norton, must be 

 assigned the credit of having first noted the sequence of the beds of 

 this interesting cutting. The beautiful species of Trigonia men- 

 tioned characterizes such horizons as the Upper Trigonia-grit of 

 the Cotteswolds and the Grey Limestone of Yorkshire. It is found 

 also, occasionally in abundance, in a quarry near the Priory Farm. 

 Many years since, it was collected in large numbers by my friend 

 Mr. Stutterd from a pit between Rollright and Hook Norton, where 

 now, however, it is rarely to be found. The fossil is associated with 

 an oyster, perhaps Ostrea calceola, Quenst., and Lima cardiiformis. 

 Some of the specimens from this region show a singular variation 

 in the area ; the upper part has solid rib-like costellae in the place 

 of the two fine costellse which ordinarily proceed from the marginal 

 nodule. The median row of tubercles has vanished, and the line is 

 shown by the inflexion of the thick Y-shaped costellse*. The late 

 Dr. Lycett was engaged in describing the Oxfordshire varieties of 

 T. signata, with several new species, for a supplement to his beauti- 

 ful monograph on the British Trigonice, prior to the illness which 

 deprived us of the aid of so skilful a paleontologist. 



The siliceous oolites which cover the whole of the Chipping-Norton 

 area, and which we have noted as covering the bed with Trigonia 

 signata, have been called by Mr. Hudleston the Chipping-Norton 

 Limestone. It is probable that they attain a thickness of 30 feet, 

 though not more than 14 feet of these beds are seen in Mr, Hudle- 

 ston's type section, the Ceteosaurus-qa&rry. 



Resting upon this limestone at Pomfret Castle, on the Banbury 

 road, is a bed of tough ragstone, from 1 to 2 feet in thickness, crowded 

 with casts of costate and clavellate Trigonice. The same bed made 

 its appearance also at the Park -corner quarry, now closed up, about 

 one mile north of Chipping Norton. Blocks, probably transported, 

 can be seen also in some disused stone-pits in Heythrop Park. Mr. 

 Windoes states that during some excavations for the Chipping- 



* The Trigonia signata from the lower part of series of Hook Norton is 

 similar to the form found at Cold Comfort, near Cheltenham. Those from 

 higher beds near RoUright are more truncated posteriorly. 



