452 LOWEU OOLITIC RO<;KS or ENGLAND : 
Ostrea flabclloides, Pectcn v ay cms, JValdheimia lagenalis, IV. 
obovata, and Echinobrissus. It here rests on bluish-grey oolitic 
limestone, which together with tho Cornbrash, is burnt for lime. 
There was no appearance of Great Oolite Clay. 
Cornbrash has been exposed here and there south of Olney 
Hide and south-west of Olney Court, as pointed out to me by 
Mr. Cameron. We there found about 6 feet of marlyand shelly 
limestones, not very fossil iferoue, but yielding Avicula echinata, 
Pecten vagans, Trigonia, Ostrea, and Waldhcimia obovata. These 
beds are seen in the railway-cutting, to rest on about 10 feet of 
Great Oolite Clay, beneath which come the rubbly and marly 
beds, and the stone-beds of the Great Oolite, all dipping west- 
wards. 
The neighbourhood of Rushden has been rendered famous as a 
locality for Cornbrash fossils by the labours of the Rev. A. \V. 
Griesbach, from whose collection the list tabulated (p. 453) was 
drawn up by Mr. George Sharman.* The quarries from which 
these specimens were obtained are no longer worked, but other 
sections are to be seen here and there along the outcrop, which 
occurs above the village of Raunds and to the east of Thrapston. 
A large quarry opened for the purpose of quarrying the Great 
Oolite Limestone, afforded a section also of the Cornbrash. It is 
situated to the south-east of Thrapston, and not far from the 
Midland railway-station. The section showed the following 
beds : 
FT. IN. 
Soil with Drift pebbles. ' 
f Kubbly and marly limestone with Wald- 
heitnia lagenalis, Ooniomya, Myaciles 
(abundant), Serpula, Holectypus de- 
Cornbrash - , ., w 77 . , 
] Bubbly marl with Waldheimia obovata 
at top, Terebratula intermedia at base ; 
) Isocardia, Ostrea, Myacites, Phola- 
[^ dornya, &c. - - - 1 
Great Oolite / Brown clay, shelly and racy - -10 
Clay. \ Dark blue clays, &c. 
The Cornbrash thus maintains its ordinary characters. Outliers 
occur to the west and south-west of Thrapston, near Islip, and 
Great and Little Addington.f Further north it extends along 
the borders of the Nene Valley by Thorpe Achurch to Overton 
Longville, near Peterborough, while large straggling outlier?, 
covered in many cases with Oxford Clay and Drifts, extend 
between Oundle and Brigstock and around Kings Cliffe.J 
The thickness of the Cornbrash in this area is stated by Prof. 
Judd never to exceed 15 feet, and it is often much less : it con- 
sists of ferruginous and earthy limestones, with marly and sandy 
beds, and is usually very fossiliferous. The more abundant 
* Judd, Geol. Rutland, p. 220. 
t Sharp, Quart. Journ. Geol. Soc., vol. xxix. p. 281. 
i Sowerby records specimens from Bulwick ; there are outliers of Cornbrash, to 
the east of the village, and south of Kings Cliffe. See also Ibbetson and Morris, 
Rep. Brit. Assoc. for 1847, p. 128. 
