1867.] BRISTOW LOWER LIAS OP GLAMORGANSHIRE. 199 



stone, but also in the more marly portion of the sands. On one side 

 of the former hill these sands are let down, and appear at a much 

 lower level ; for, as a rule, they cap the hill. In the Vale of Wardour 

 they seem to have been mostly denuded ; but blocks of ironstone 

 derived from them are scattered about the fields in places, in the 

 same way as the chalk-flints are, owing to the previous denudation 

 of the chalk hills. 



4. On the Lower Lias or Lias -Coin^glomee ate of a part of Glamoe- 

 GAxsHiEE. By He^iy W. Bristow, P.R.S., F.G.S., of the Geolo- 

 gical Survey of Great Britain. 



Ox the 6th December, 1865, a paper was read before the Society, 

 by Mr. E. B. Tawney, " On the Western Limits of the Rhsetic Beds 

 in South "Wales, and on the position of the ' Sutton Stone ' "*. 



The chief object of the above communication was (to quote the 

 author's own words), " to discuss the ^Sutton Stone' as to its strati- 

 graphical, Hthological, and palseontological relations ; to show from 

 organic remains that its affinities were with the Triassic formation, 

 and not with the Lias, as commonly supposed, and then to claim it 

 as Ehsetic, and in so doing to extend, for the first time in England, 

 the range of Ammonites down into the Ehaetic series " (p. 70). 



In order to render his views still more intelligible, the author 

 reiterates (at p. 72 of his Memoir), " These beds I now claim as 

 Rhsetic, and would unquestionably separate from the Lias. As 

 developed on the coast, they are between 80 and 90 feet in thick- 

 ness : to the lower half of this the term ' Sutton Series ' may apply ; 

 and for the upper half I propose the name of ' Southerndown Series,' 

 as they are best seen in the fine chff-exposure under the hamlet of 

 Southerndown." 



In further elucidation of the views already expressed, the author 

 gives two sections at p. 75 — one a vertical section representing, in 

 the lower part, 39 feet of the " Sutton Series " overlain by a thick- 

 ness of 50 feet 9 inches of "■ Southerndown Series," which, again, is 

 surmounted by acknowledged Lias, represented by the zone of 

 Ammonites BucMandi, the lowest part of that series. 



I have considered it necessary, thus fully, to remind the Society 

 of the bearing of Mr. Tawneys communication, in order that the 

 remarks which I wish to bring before them, in reference to this very 

 interesting series of deposits, may be more clearly understood. 



On resuming my duties in the field, in the course of the past 

 summer, for the purpose of extending the survey of the Penarth or 

 Ehaetic series westward of the district where I had been compelled, 

 by stress of weather, to abandon their examination at the close of 

 the previous year, I was induced to give the preference to the 

 locality treated of by Mr. Tawney, rather than to Watchett (where I 

 had examined and measured the sections in detail, with my colleague, 

 Mr. Etheridge, in order to map the strata in question), and while 



* Quart. Journ. Geol. Soc, vol. xxii. p. 69. 



