1873.] 



SHARP OOLITES OP NORTHAMPTONSHIRE. 



281 



6. "Best building-stone" — hard crystalline blue-hearted 



limestone, full of comminuted shells, worked into lintels 

 and sills of windows, quoinings, &c 



7. Marly limestone, full of shells 



8. Very hard blue-hearted crystalline limestone, full of 



comminuted shells (small Pteropcrna), used for road- 

 metal 



9. Upper Estuarine Clays. 



Fossils. 



ft. 



2 6 



Modiola imbricata, Sow. 

 'Trigonia Moretoni, Mor. 8[ Lye. 

 Rhynchonella concinna, Sow. 

 Belemnites (small). 

 Strophodus magnus, Ag. (palate). 

 Ophiurella Griesbachii, Wright. 



Lima cardiiformis, Sow. 



, sp. (like, but not, duplicata, 



Sow.) ? 

 Ostrea Sowerbyi, Mor. $ Lye. 



sub-rugulosa, Mor. Sf Lye. 



Pecten lens, Sow. 

 Pteroperna, sp. ? 



Thrapstone to Northampton. 



North of Thrapstone and Islip, the high ground has a thin 

 capping of Cornbrash ; beneath which, upon a western escarpment, 

 crops out the same sequence of beds as that with which I commenced 

 my descriptions, viz. — 



Great Oolite Limestone. 

 Upper Estuarine Series. 

 Lower Estuarine Series, 

 Ferruginous Beds, 

 Upper Lias Clay. 



I Northampton Sand. 



And the same sequence again and again occurs throughout the 

 district intervening between Islip and Northampton. 



Cypricardia nuculiformis, Bomer. 

 Modiola imbricata, Sow. 

 Ostrea Sowerbyi, Mor. Sf Lye. 

 Pvhychonella concinna, Sow. 



Great Oolite Fossils from Thrapstone. 



Terebratula intermedia, Sow. 



maxillata, Sow. 



Echinobrissus clunicularis, Lhwyd. 



Cornbrash Fossils from Islip. 



Terebratula lagenalis, Schloth. 



obovata, Sow. 



, new sp. 



Echinobrissus orbicularis, Phil. sp. 



Cypricardia caudata, Lycett. 

 Modiola Lonsdalei, Mor. $ Lye. 

 Myacites decurtata, Goldf. sp. 



securiformis, Phil, sp, 



, sp. ? 



The Ferruginous beds become thicker and richer at Woodford, 

 Cranford, Finedon, Wellingboro', and other neighbouring places. 

 The quarrying of ironstone has greatly increased in Northampton- 

 shire during 1872 ; a quantity exceeding 20,000 tons being at this 

 time (November, 1872) weekly raised in the county. 



Conclusion. 



The geological phenomena of the numerous localities described 

 have served, I would submit, to establish the following Propo- 

 sitions : — 



