Mr. E. Tawney on the Rhcetic Beds in South Wales. 157 



December 6, 1865. — W. J. Hamilton, Esq., President, in the Chair. 



The following communications were read : — 



1. " On the Western Limit of the Rhaetic Beds in South Wales, 

 and on the position of the Sutton Stone." By E. B. Tawney, Esq., 

 F.G.S. With a Note on the Corals of the Sutton Stone, by P. 

 Martin Duncan, M.B., Sec. G.S. 



Mr. Tawney commenced with a description of the Rhaetic beds 

 as they occur near Pyle station, west of Bridgend, and at Cwst y 

 Coleman, north-west of that place, giving detailed sections of the 

 beds at these localities, and showing the distribution of the fossils 

 in them. The author then described the characters of the " Sutton 

 Stone," and showed its relations to the beds above and below, giving 

 to the building-stones generally called "Sutton Stone" the name 

 " Sutton Series," and to the beds which intervene between the Sutton 

 Stone and the base of the true Lias, and which have hitherto been con- 

 sidered Lias, the name " Southerndown Series," illustrating the stra- 

 tigraphical features by a general section from Sutton to Dunraven 

 Castle, and by vertical sections at Southerndown and Laleston. 

 From the evidence yielded by the fossils, the author was of opinion 

 that the Southerndown series belonged to the Rhaetic formation, 

 and must be separated from the Lias — that the Sutton series is some- 

 what older than the Avicula-contorta beds, and has affinities with the 

 Trias — and that, by the discovery of Ammonites in the Sutton beds, 

 the first appearance of that genus in the British area has been 

 proved to have occurred during a period anterior to the Lias. 



In his note on the Corals, Dr. Duncan stated that, besides two 

 species derived from the Carboniferous Limestone, he had been able 

 to determine four species of Zoantharia from the base of the " Sutton 

 Stone." These Corals are unlike any hitherto discovered in North- 

 western Europe, and, with certain reservations, were said to indi- 

 cate an horizon which, in the Alpine Triassic districts, would be 

 deemed St. Cassian ; but, as our knowledge of the vertical range 

 of the St. Cassian Corals is at present very imperfect, their absolute 

 age cannot be more definitely stated, their occurrence in South 

 Wales rendering it probable that they have a greater vertical, as 

 they are now proved to have a greater horizontal, range than has 

 hitherto been supposed. 



2. " Notes on a Section of Lower Lias and Rhaetic Beds near 

 Wells, Somerset." By the Rev. P. B. Brodie, M.A., F.G.S. 



A section recently exposed at Milton Lane, one mile and a half 

 north of Wells, exhibited the Lima-beds passing into and overlying 

 the White Lias and Avicula-contorta zone. The author described 

 the section (which was constructed by Mr. J. Parker and himself) 

 in detail, and showed that the Lima-series attained here a thickness 

 of 10 feet 4 inches, and the Rhaetic beds, including the grey marls, 

 of 18 feet 6 inches ; he was not able to discover any trace of Am- 

 monites planorbis, or of any of the peculiar limestones indicating the 

 "Insect" and "Saurian" zones. He found one fragment from a 



