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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Apr. 9 f 



April 9, 1851. 

 The following; communications were read : — 



1. On the Basement Beds of the Inferior Oolite in Glouces- 

 tershire. By the Rev. P. B. Brodie, M.A., F.G.S. 



The lower strata of the Inferior Oolite, near Cheltenham, and in 

 other parts of Gloucestershire, present some features of novelty and 

 interest, which I now proceed to lay before the Society ; and this will 

 form a conclusion to my previous paper on the superior Divisions of 

 this Formation*. The bed immediately below the " shelly freestone" 

 has been correctly termed Pisolite or Pea-grit in the 'Geology of 

 Cheltenhamf,' and is there described as being "made up of small 

 flat concretions from a quarter to half an inch in diameter, which 

 give it the appearance of a nummulitic rock." At Leckhampton Hill 

 it admits of the following subdivisions : — 



Feet. 



f A. — Rubbly, coarse, pisolitic Oolite, the flat concretions rather large ; 

 in places much broken up, though some large blocks occur at in- 

 tervals ; prevailing colours yellow and brown. It contains some 

 Corals and several species of Echinodermata, among which Pygaster 

 semisulcatus, Phill. (Clypeus ornatus, Buckman) and Hyboclypeus 

 agariciformis, Forbes, are characteristic 11 



B. — Hard, whitish, compact Oolite, called " Weatherstone " by the 

 workmen ; the flat concretions somewhat smaller than the above. 

 It is a good useful stone, and stands the frost. Many beautiful 

 Corals are scattered over the surface of the blocks 8 



C. — Coarse, concretionary, ferruginous Pisolite, with very large grains ; 

 a loose rubbly bed, like No. 1 ; Shells and Corals numerous ; passing 

 into a hard rough Oolite, less pisolitic in its structure than any of 

 the above; varying in colour, brown and yellow predominating; 

 fragments of Trichites, Terebratula simplex t, T.plicata, T.tetra- 

 hedra, Triyonia, Pectines, Amphidesma, and other fossils abundant, 

 and occasionally claws of Crabs § 19 



Total 38 



* Quart. Journ. Geol. Soc. vol. vi. p. 239 et seq. 



A description of the new species of shells in the " shelly freestone " is given in 

 Mr. Lycett's valuable paper in the Annals of Natural History, vol. vi. No. 36, for 

 December 1850. 



1 scarcely did justice to my friend Professor Buckman in my late communication 

 upon the " shelly freestone," for I inadvertently omitted to state that he had pre- 

 viously remarked the identity of some of the Testacea with Great Oolite species, 

 although the number referred to was at that time very small (see Geology of 

 Cheltenham, p. 31). 



f Outline of the Geology of the Neighbourhood of Cheltenham, by R. I. Mur- 

 chison, 2nd edit. Augmented and revised by James Buckman and H. E. Strick- 

 land. 8vo. 1845, pp. 26 and 31. 



% Terebratula plicat a and T. simplex are most prevalent in the Pisolite, and do 

 not occur below it ; the latter is often of large size. 



§ A new form of the minute Brachiopod, Thecidea, occurs in the Pisolite, which 

 Mr. Davidson considers to be a variety of Th. triangularis, D'Orb. and Dav. ; the 

 latter is frequently found attached to Corals in the Oolite-marl. Several other 

 new species of shells have been discovered in the Pisolite (especially by my friend 

 Dr. Wright), but they are at present unnamed. 



