ROCKS OJ? SOMEK8ET Am) DEVON. 371 



change, or to afford intercalations of calcareous matter other than 

 is locally to be seen in certain of the lowermost breccio-conglomerates 

 in the neighbourhood of Sampford Peverell (vide Conybeare and 

 Phillips, ' Outlines of Geology of England and Wales,' p. 308), and 

 in the vicinity of Paignton and Teignmouth, in the middle series of 

 conglomerates near Wiveliscombe, Milverton, and Veilow (near 

 Stogumber), and the marlstones between Bishops Lydeard and 

 Crowcombe Reathfield, and the calcareous nodules and beds in the 

 same sandstones in other places. The fragments contained in the 

 conglomerates are principally composed of Carboniferous limestone, 

 exhibiting various degrees of attrition, from well-rounded boulders 

 and pebbles to nearly angular fragments. 



At Wrington (near Yatton) and Draycot (near Cheddar) beds 

 rather approaching to the character of a breccia than a conglomerate 

 occur, and in the latter locality form a very serviceable building-stone. 



Organic Remains. — Sir H. De la Beche, in the Avork before cited 

 (p. 268), says : — " In the dolomitic or magnesian conglomerate of 

 Redland, near Bristol, Dr. Riley and Mr. Stutchbury have found the 

 remains of two Saurians, to which they gave the names of Thecodon- 

 tosaurus and Palceosaums" (Vide Moore, "Abnormal Secondary 

 Deposits," I. c. p. 456.) 



We may therefore infer that, from its first known appearance 

 in the Coal-measures, Sauroid life had continuously progressed 

 through the Triassic period (of which Mr. Lavis's recent interesting- 

 discovery at Sidmouth affords further proof) wherever the waters of 

 that period were favourable to their existence, till in the Liassic 

 age more suitable conditions for their preservation, if not for their 

 increase, prevailed. 



Thickness. — According to Conybeare and Phillips (p. 299), " At 

 Pucklechurch, in Gloucestershire, shafts have been sunk from the 

 Lias to the coal-measures ;" the Trias was found to be 153 feet in 

 thickness. 



In a section of a coal-pit, | mile south-east of the village of 



Paulton (ibid. p. 429), the Trias underlying Liassic and Oolitic beds 



was found to consist of — ., . 



ft. in. 



Bed inarl and sand 132 



Calcareo-magnesian conglomerate, called millstone 6 



Total thickness of Trias... 138 



In a pit-section at Chilcompton, given by Messrs. Buckland and 

 Conybeare (in observations on the south-western coal-district), the 

 dolomitic conglomerate continued for 138 feet from the surface. 

 (It should be mentioned that the major part of the formation in this 

 locality is represented by conglomerates, and that, in places, the 

 Phytic beds appear to rest directly upon them, so that the formation 

 of conglomerate appears to have been locally continuous and con- 

 temporaneous with that of the upper beds of marl.) 



The same observers give a section of a pit at Welton, to the 

 north of Midsomer Norton, which was sunk through 114 feet of 

 red marl, resting on 6 feet of dolomitic conglomerate. 



