in the Bunter of West Somerset. 161 



Combe Florey this division of the New Ked Sandstone Series is 

 generally I'epresented by a conglomerate composed of pebbles of 

 limestone, quartz, and grit, more massive in its lower part.^ For some 

 distance north of Combe Florey the upper beds of the division are 

 faulted out and the lower beds are represented by a loose, rubbly 

 gravel of subangular fragments of Devonian grit in an earthy or sandy 

 matrix. The conglomerate reappears at Yellow, near Stogumber, and 

 is found in several places in the Williton district, whilst in other 

 places it is represented by gravels, sands, and sandstones. 



The influx of limestone and grit pebbles which takes place north of 

 Burlescombe has usually been referred to the degradation of the Culm 

 limestones and Devonian rocks. ^ The study of the distribution of the 

 minerals in the matrix of the Pebble-bed and conglomerate between 

 Budleigh Salterton and Milverton lent support to this view, and led 

 Mr. H. H. Thomas to deduce the existence in the Bunter period of 

 a main sediment-bearing current from the south, joined by a minor 

 current from the west in the neighbourhood of Burlescombe.^ It is 

 difficult to believe, however, that the large quantity of limestone in 

 the conglomerate between Thorne St. Margaret and Combe Florey has 

 all been derived from the comparatively small ioliers of Culm lime- 

 stones near Burlescombe, or from the thin and impersistcut limestones 

 occurring to tlie west of the district, especially in view of the fact that 

 the Culm inliers are surrounded by Lower New Red deposits, and 

 they cannot, therefore, have occupied a larger area in Bunter times 

 than they do now. 



In the case of the massive conglomerates of the Williton district the 

 difficulty of referring the limestone pebbles contained in them to the 

 Devonian rocks of the surrounding area seems to have been felt by 

 De la Beche, who suggested that " compact grey limestones probably 

 occur beneath the red sandstone series near Sampford Brett and 

 Stogumber, for red conglomerates there worked for lime abound in 

 rounded stones and pebbles of a grey compact limestone".* 



The Carboniferous Limestone to the north and north-east appears 

 to be a much more probable source for the limestone pebbles in the 

 conglomerate. Neglecting the Cannington Park inlier, which lies 

 on the east side of the Quantock Hills, the nearest exposure of 

 Carboniferous Limestone is about 15 miles north-east of Williton, or 

 no further than the Culm limestones on the south. In the south 

 of Glamorgan Keuper, Rhsetic, and Liassic deposits successively 

 overlap one another and rest directly on the Carboniferous Limestone, 

 each of the newer deposits assuming a peculiar ' littoral ' facies in 

 the vicinity of the older rock.^ During the Bunter period South 

 Glamorgan was evidently a land area formed chiefly of Carboniferous 



1 Memoirs of the Geological Survey: "Geology of the Quantock Hills, etc.," 

 1908, p. 46. 



2 Ibid. : " Geology of the Country between Wellington and Chard," 1906, p. 14. 

 ^ H. H. Thomas, "B. A., F.G.S., "The Mineralogical Constitution of the Finer 



Material of the Bunter Pebble-bed in the West of England " : Q.J.G.S., 1902, 

 pp. 620-32. 



* Report on the Geology of Cornwall^ Devon, aiid West Somerset, 1839, p. 55. 



5 Memoirs of the Geological Survey : ' ' The Geology of the Country around 

 Bridgend," 1904, ch. v. 



DECADE v. VOL. VI. — NO. IV. H 



