MOOEE — ABNOKMAL SECONDARY DEPOSITS. 507 



beds, which is generally very dense, shows that it may be almost 

 denominated a Foraminiferal Reef. It is almost entirely composed 

 of minute organisms ; and four or five genera of Foraminifera may 

 be detected within a square inch, and also Entomostraca. The for- 

 mer include Involutina, Dentcdina, Crlstellaria, Nodosar'ia, Planu- 

 Una, &c. The number of species cannot be arrived at, as they are 

 generally broken across. 



It may be noticed that along the railway-section no beds are 

 present which have the lithological character of the Sutton stone ; 

 and, except that the upper ones are rather more arenaceous, and are 

 more closely bedded, they are in the usual condition of the Lias ; but 

 as they meet the Carboniferous Limestone the Sutton-stone charac- 

 ter appears. 



Looking across from the railway towards the Mendips, a large 

 quarry of Carboniferous Limestone may be observed at Windsor 

 Hill. In passing through the town in this direction, in about a 

 mile, a roadside-section of considerable interest is reached, which 

 has been noticed by Sir Henry de la Beche in his memoir on the 

 '' Formation of the Kocks of South Wales and South West of Eng- 

 land," p. 278*. The town of Shepton Mallet is cut across by several 

 ravines ; and there is little doubt that the Carboniferous Limestone 

 is not far below the surface, and that it again formed the sea-bottom 

 of this district during the Liassic period. 



The road to Windsor Hill passes up a small ravine on the south 

 of the Mendips ; and a short way out of the town we reach a series 

 of thickly bedded Liassic rocks, without any clay partings, extend- 

 ing for a length of 96 feet, the beds dipping south towards the 

 town. This portion of the section is cut off by a fissure contain- 

 ing crystalline carbonate of lime, 1 foot wide, from a continuation 

 of the same beds (but dipping at a less angle), 84 feet in length. 

 Another vein of 1 ft. 4 in. separates this block from more thickly 

 bedded rocks, which are nearly horizontal, 114 feet in length. A 

 wall of 42 feet succeeds, which has probably been built against dis- 

 turbed and broken rocks, and covers the connexion of the latter 

 beds with another vein 2 feet thick, which at this point separates 

 the Lias from a section of Carboniferous Limestone, which extends 

 for a distance of 120 feet, and which is seen to be continuous in 

 thick-bedded limestones on the opposite side towards Cowl Street. 

 At the upper end of this Carboniferous Limestone there rests im- 

 mediately upon it several thin beds of conglomerate, 1 foot in 

 thickness, belonging to the Ehaetic bone-bed, and perfectly identical 

 Avith the conglomerate I have before noticed at Hapsford Mills. 

 It is composed of rounded pebbles, mixed with which are many 

 Eha3tic teeth and bones. The littoral character of this deposit may 

 be seen when it is mentioned that, in a block a few inches square, 

 I have a fine vertebra of Plesiosaurus rugosus (?), teeth of Acvodus, 

 Avicula contorta, and abundance of bones, and Carboniferous-Lime- 

 stone, Encriintes. 



* Mein. Gcol. Survey, vol. i. 



