456 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, 



object was to make good tlie interval between North Wilts and the 

 country where Dr. Fitton states that he resumed his observations 

 (p. 2/0). What seemed to render this district more peculiarly in- 

 teresting, was the circumstance that it included the beds at Farring- 

 don, so well kno^vn from their fossils, as far back as the catalogue of 

 Llwyd [1759] ; described by Dr. Fitton as " outlying masses of lower 

 greensand," and considered by him to be especially deserving of 

 notice (p. 2/1) ; also that pubhshed lists afforded indications of fossil 

 forms peculiar to this portion of the cretaceous series, and limited 

 to a few localities, and which seemed to present a wide departure 

 from the ordinary conditions which influenced the lower cretaceous 

 deposits ; such as the numerous and perfect Amorpliozoa at Far- 

 ringdon, several forms of Terebratula to be noticed in the sequel, and 

 Diceras Lonsdalei, Sow. 



In the present state of our information, the district we proposed 

 to examine included all the localities at which the reputed beds of 

 lower greensand were reported as fossihferous ; whilst the lists of the 

 fossils from the several places contained such an apparent admixture 

 of the forms of distinct geological epochs, as to make it an interest- 

 ing inquiry how far the ooUtic blended with the cretaceous fauna even 

 in this country. 



§ 1. Farringdon. 



We commenced our observations at Farringdon, following the in- 

 dications contained in the * Geology of England,' that at that place 

 ''are two summits of ironsand, one on the east of the town, marked 

 by a conspicuous clump of firs, the other on the south-west " (p. 1 90). 

 Farringdon Clump is a conical mass, crossed on its south slope by the 

 high-road from the railway station ; on the upper side of the road is 

 a good section of the beds which compose the hill at this level, con- 

 sisting of pale yellow stratified sands ; at a rather lower level, a brick- 

 yard has been established on beds of clay, and the sands which 

 immediately overlie the clay contain subordinate concretionary sand- 

 stones. No pits are worked in any portion of the hill above the road ; 

 but from the character of the cultivated ground, it is evidently wholly 

 composed of sand. Crossing over the hill, the sands descend to the 

 highway road which passes it on the north, and are followed by a 

 breadth of cultivated clay land resting on coral rag, which forms a 

 low ridge above the valley of Oxford clay. Some large pits are 

 worked in the calcareous coral rag, just at the entrance of the town of 

 Farringdon, on the east, and these are interesting from the alternations 

 which the upper portion of the coralline strata presents with bands of 

 blue clay, and from the disturbances which seem to have repeatedly 

 taken place — indicating somewhat more than ordinary submarine 

 action, previous to the establishment of those conditions which fa- 

 voured the deposition of the superincumbent clays. 



It is mamly from the manner in which the lower portion of this 

 mass of clay is associated with the top of the coral rag — one so com- 

 monly occuning with respect to the different component mineral 

 groups of all great geological formations — that we are disposed to 



