154 



Many of the specimens at the time of the discovery were 

 exhibited to the Club by onr old friend, Mr, John Jones, late 

 of Gloucester. Montlivaltia, Isastrcea, Tliamnastrcea, and Stylina, 

 are represented by several new species in this collection. The 

 Combrash near Chippenham has yielded a few specimens of 

 Cladophyllia. 



The Oxford Clay afforded many Ammonites, but no Corals ; 

 in France, however, some species have been found. Like 

 the Lias, future observers may yet discover that this great 

 argillaceoiis formation is not destitute of Actinozoa. 



The Coral Bag. — This formation has long been considered to 

 be the great metropolis of Jurassic Corals; and although in 

 certain regions reef structures are found, the specimens are 

 for the most part collected from beds that crop out at the 

 surface of arable lands. The number of species found in this 

 formation is by no means proportionate to the individuals 

 collected therefrom. After a cai-eful study of all the best 

 British Coral Eag specimens, MM. Edwakds and Haime could 

 only make out fourteen species, of which twelve belonged to 

 the Astrceidce, and two to the Fungidce; five of these were 

 identical with the Coral Eag of France and Germany, and 

 nine are found as yet only in British strata. The principal 

 localities for Corals from this formation are Steeple Ashton, 

 Wilts ; Osmington, Dorset ; Upware, Cambridge ; and Malton, 

 Hackness, Ayton, and Seamer, Yorkshire. 



The Coral Eag in Wiltshire is divisible into ( 1 ) Upper 

 Calcareous Grit, (2) Coral Eag, (3) Clay, (4) Lower Calcareous 

 Grit. It is in the Coral Eag proper (2) that the Coral beds 

 are found. Of these Mr. Lonsdale " remarks, " the irregular 

 beds of Polyparia (2c) consist of nodules or masses of 

 crystallized carbonate of Lime, which afford, invariably, 

 evidences of the labours of the Polypus, and associated with 

 them are others of earthy Limestone, which bear only partial 

 proofs of an organic origin. The whole are connected by a 

 pale blueish or yellowish stiff Clay. It happens frequently that a 

 bed is composed of one genus of Polyparia. At Cahie and 



1* Oolitic District of Bath, Trans. Geol. See. , second series, vol. iii, p. 261. 



