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up the fractured sui-face. Another exposure, however, showed 

 the true position of the Corals. A few years afterwards the 

 same bed was opened near the Seven Springs, and a large 

 quantity of road material was raised therefrom, consisting 

 chiefly of blocks of Limestone, full of Corals. My friend, the 

 Rev. P. B. Bkodie, and myself, made several journeys to these 

 road heaps, for the pui-pose of collecting specimens. The best 

 exposiire of this Coral reef is near Frith quarry, on the northern 

 spur of Brown's Hill, about two miles from Stroud, and visited 

 by the Club last year. The Coral reef formed then a complete 

 bluff of Coral rock ; since that time, however, much of it has 

 been removed for road-mending. Still enough remained on the 

 31st May to enable my friend, W. C. Lucy, Esq., F.G.S., and 

 myself, to make a re-examination of the reef, in order to give a 

 finishing touch to my former notes. This Coral bed is upon the 

 same horizon as the Coral bed on the opposite side of the valley, 

 at Huddinknoll Hill, near the Horsepools, the whole of the 

 intervening space having been removed by denudation. The 

 Coral bed consists of large masses of Coralline Limestone, 

 embedded in a fine grained cream-coloured Mudstone. The 

 Corals are in a highly crystalline state, so that the genera and 

 species are determined with difficulty, unless when they are 

 found in portions of the rock that have been weathered. The 

 bed is fi'om 15 to 20 feet in thickness, and forms one of the 

 finest examples of a fossil Coral reef that I am acquainted with 

 in our district. On the western side of the valley the same bed 

 is exposed, and worked for the roads ; and several miles of the 

 highway fi*om the Horsepools to Gloucester is repaired with the 

 product of this lower Coral reef of the Inferior Oolite. The 

 bed may be traced along the escarpment, in a north-westerly 

 direction, for several miles, to Witcomb and Crickley on the 

 west, and to near Cubberley and Cowley on the east, where it 

 was worked several years ago. Judging from the thickness of 

 the bed, and the abundance of Corals it contains, it must have 

 formed a Barrier reef of considerable magnitude in the Jurassic 

 sea. The following section wiU best exhibit the true relation of 

 the Coral reef to the underlapng and superinc\imbent strata: — 



