460 Morris — Ferruginous Sands of Buckinghamshire. 



and sponges, some similar to those at Farringdon, and also rolled 

 specimens derived from older rocks, my friend, Mr. Huddlestone, 

 r.G.S., has shown me a fine series collected from this bed.' 



At Ely and Haddenham these sands rest on the Kimmeridge clay.^ 

 Further northwards, in Lincolnshire, a change takes place in the 

 mineral character of the beds, presenting somewhat an approximation 

 to the southern type. Mr. Judd ^ has described the strata, overlying 

 probably, the Oxford clay, near Market Easen and Tealby, to 

 consist of — • 



1. Upper ferruginous sands, non-fossiliferous, twenty feet thick. 



2. Tealby series, alternate beds of sandy clay and limestone, with 



many fossils, forty to fifty feet. 



3. Lower sand and sandstone, with few fossils, thirty to forty feet. 

 A somewhat similar arrangement of the strata below the Eed 



Chalk in Lincolnshire, was proposed by Mr. Conybeare, in 1822, viz. 

 L Quartzose, ferruginous, pebbly sand, from eight to ten yards. 



2. Calcareous clay, containing beds and concretions of Oolitic lime- 



stone, from twelve to fourteen yards. 



3. Granular quartzose sandstone and sand, varying from dark -brown 



to light-grey, and containing shells, considerably thicker 

 than the two former beds. 



These beds rest on strata of argillaceous shale, which appear to 

 belong, in part at least, to the Oxford clay.* 



Crossing the Humber the equivalents of these beds pass under 

 the Wolds, and again reappear at the well-known section of Speeton, 

 long ago described by Professor Phillips, in which the mineral 

 character again differs from that of Lincolnshire and Bedfordshire. 

 This is the most northerly extension of the Lower Cretaceous rocks, 

 which here are considered to overlie the Kimmeridge clay. 



In a westerly and south-west direction from Aylesbury the Lower 

 Greensand may be traced, but not always continuous, at BrilP 



1 Walker, Geol. Mag., Vol. IV. p. 309. 



2 Sedgwick, Lecture on the strata near Cambridge, Dec, 1861, p. 21. 



3 Quart. Journ. Geol. Soc. vol. xxiii. p. 243. In the year 1859, during a visit to 

 tMr. Morel, at Bayons Manor, I traced out, with Mr. T. J. Smith, F.G.S., of Hull, 

 the characters of the Lower-green Sand around Tealby, from Hainham to Caistor, 

 and pointed out the existence of the pisolitic iron ore then unworked at Walesby, 

 and arrived at the conclusion that these beds and their fossils, as well as those at 

 Speeton, should be carefully compared with the Hilstlion and Hilsconglomerat of JS. 

 Germany (Hanover), and not with the Portland, as suggested by a geologist. I col- 

 lected many fossils, such as the large Feeten, Ancyloceras, Trigonia, Belemnites, etc , 

 some of which are now in the British Museum. A general sketch of the geology of 

 the locality mentioned was given in the introductory lecture that I had the pleasure 

 of giving at the opening of the Tealby Institute (Nov. 29, 1859), established by the 

 late Tennyson D'Eyncourt, Esq. I subsequently examined, in company with Mr. 

 Prestwich and Mr. S. Sharp, the district around Spilsby and Horncastle, etc., and 

 found in the sands at the former place specimens of Coniferous wood with Teredo 

 borings and also phosphatic nodules. Mr. R. Godwin Austen considered the Speeton 

 clay to be the representative of the Hiisthon (Proc. Geol. Soc. vol. iv. p. 196). See 

 also Roemer, Die Versteinerungen des Norddeutschen Kreidegebirges, Hanover, 

 1840. 



* Outlines of Geology, 1822, p. 164. 



6 Fitton, Geol. Trans., Vol. iv. p. 280. Estuarine sands with Paludina, Brodie, 

 Quart. Journ. Geol. Soc, Vol. xxiii, p. 198. 



