1873.] 



SHARP — OOLITES OP NOETHA.MPTONSHTEE. 



249 



hardly to be over-estimated advantage of a complete sequence of 

 beds, ranging downwards from the Cornbrash to the Upper Lias in- 

 clusive. Here the beds tell their own tale, leaving little for surmise 

 or for question as to their identity or order *. 



Eecent operations in connexion with enclosure led to the opening, 

 at the highest point, of a shallow pit ; thus exposing a section of 

 Cornbrash, having a thickness of about four feet, seldom greatly ex- 

 ceeded in the district. Prom the stone of this pit, I obtained some 

 usual Cornbrash fossils : — large Ostrea Marshii, Sow., Terebratula 

 sub-lagenalis, Dav., Dentalium entaloicles, Deslong., Echinobrissus 

 orbicularis, Phil., &c. &c. 



The Great Oolite Clay underlies the Cornbrash, although not ex- 

 posed in any section. Below this, are beds of the Great Oolite 

 Limestone ; from which I have obtained : — 



Ammonites, sp. ? 



— — gracilis, Buckm. (large), 



Nautilus Baberi (?), Mor. § Lye. (large 



septum). 

 Clypeus Miilleri, Wright. 



Avicula echinata, Sow. 

 Ceromya concentrica, Sow. 

 Modiola imbricata, Sow. 

 Ostrea Sowerbyi, Mor. $ Lye. 

 — sub-rugulosa, Mor. cf Lye. 

 Rhynchonella concinna, Sow. 



Lower beds of this Limestone are seen at the top of the section 

 in Torkington's brick-pit, overlying the extremely various and varie- 

 gated beds of the Upper Estuarine Series ; which consist here of — 

 a reddish sandy bed, coarse shelly clay with plants, pale grey clay 

 streaked with exceedingly shelly seams (sometimes containing Cyrena 

 and similar freshwater or estuarine shells, and sometimes Necera 

 Ibbetsoni, Pholadomya acuticosta, Modiola imbricata, &c), dark blue 

 clay (shells with their tests preserved), and dark chocolate laminated 

 clays. 



These Estuarine beds have an aggregate thickness of about 27 

 feet, and are based by the ferruginous band ; here strongly pro- 

 nounced, and peculiar in its rather open structure, and in the pre- 

 sence of much wood. 



Section in Torkington's Brick-pit, Stamford Field. 



1. Great Oolite Limestone — 



ft. in. 



a. Limestone 1 



b. Sandy stone '. 1 



c. Grey clay 1 



d. Very soft marly white stone {Rhynchonella con- 



cinna, Modiola imbricata, Ceromya concentrica)] 9 



2. Upper Estuarine Series — 



a. Eeddish sandy bed, in layers, sometimes passing 



into a " caley " stone 4 



b. Coarse shaly clay, with plants 3 



c. Grey clay, in layers full of shells {Cyrena, Necera 



Ibbetsoni, Pholadomya acuticosta, Modiola imbri- 

 cata, Ostrea, &c), and containing plants and 

 wood 2 



ft. in. 



3 9 



* See Diagram of Section, Plate X. fig. 1, 



