PEOM THE GEEAT OOLITE. 175 



Across the valley, eastward of tlie Hampton Downs, near to the 

 village of Bathfoid, and directly under the building called Brown's 

 Tower, is a quarried escarpment which constitutes the western 

 boundary of Parley Down. From this spot, as I learn from the 

 Eev. H. H. Winwood, the late Mr. Walton obtained his Parley- 

 Down fossils. 



The coral-bed is here more fully developed than in the Hampton- 

 Down quarry, or than at the Hampton Hocks. Yarying-iu thickness 

 from two feet to ten feet, it possesses all the peculiarities observable 

 in such Inferior-Oolite coral-deposits as Crickley and the Horsepools, 

 near Cheltenham, being a fine-grained and light-coloured mudstone, 

 which in some places is somewhat brecciated. It corresponds pre- 

 cisely in position with the coral-beds on the south-west side of the 

 valley, appearing immediately above the massive building-stone. 

 Iq several places above the escarpment, where the surface of the 

 turf has been broken through, thin patches of Porest Marble are 

 exposed ; and it would therefore seem that as the coral-bed occurs 

 only a little way below that bed, and as it contains many fragments 

 of the well-known Bradford-clay Encrinite, it holds a higher 

 geological position in the Great Oolite than has been assigned to the 

 Oxfordshire coral-beds, if we except the one at Caps Lodge near 

 Burford. Prom the Parley-Down exposure I have obtained the 

 following corals : — 



Stylosmilia reptans, n. sp., Stylina Ploti, Grytocoenia micropJiylla, 

 Convexasfixea Waltoni, Heliocoenia oolitica, n. sp., Montlivaltia caryo- 

 phyllata, Isastrcea Umitata, I. explanulata^ I. microphyUa, I. sp., 

 Latimceanclra loiJiaringa, CJiorisastrcea ohtusa, Goniocora, sp., Tham- 

 nastrcea scita, T. Waltoni^ Comoseris vermicularis, Oroseris Slatteri, 

 Dimorpharcea, sp., Anahacia comjjlanata, Microsolena excelsa. 



AH the species from this, as well as other places in the Bath 

 district mentioned in this paper, have been obtained from their 

 respective localities and beds by Mr. T. J. Slatter and myself. 



EisTALLOHELiA sociALis, u. sp. (Plate Y. figs. 13, 14.) 



The corallum consists of a great many corallites proceeding from 

 a common root, which is of small extent. Prom this they grow 

 upward and outward in every direction, and form a very thick and 

 tangled mass from one to two inches in height, and three or four in 

 breadth. This has a very irregular but somewhat convex upper 

 surface, formed by the union of the corallites, which are thus fused 

 into a more or less compact mass. The corallites are thin and 

 maintain nearly the same diameter throughout. They ramify in an 

 irregularly alternate manner, but do so very much more thickly at 

 their upper ends, where, coming into contact with others, many 

 unite and form irregular masses, which have their upper surfaces 

 more or less flattened. The mural costae, which in some species of 

 this genus are observable near the calicos, and in connection with 

 the septa, are in the present species nearly obsolete. 



Yery few calicos appear on the lower part of the corallites, but 

 on the upper surface they are thickly but irregularly scattered. All 

 the prominent ends of the corallites, and aU the axial spaces have 



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