Vol. 67.] THE CARBONIFEROUS SUCCESSION IN GOWER. 477 



17. The Carboniferous Succession in Gower (Glamorganshire), 

 luith Notes on its Fauna and Conditions of Deposition. By 

 Ernest Edward Leslie Dixon, B.Sc, A.R.C.Sc, E.G.S., and 

 Arthur Yaughan, M.A., D.Sc, E.G.S. (Read March 9th, 

 1910.) 



[Plates XXXVIII-XLL] 



Contexts. 



Page 



I. Introduction (with Maps on pp. 478-79) 477 



II. Lithological Characters of the Zones (E. E. L. D.) 480 



(1) Eastern District, 



(2) Norfch-Western District. 



(3) South-Western District. 



(4) Tabulated Synopses of the Sequence : — (i) in each District ; 



(ii) generalized for the whole Area. 



III. Note on the Pseudobreccias of the D-Zone (E. E. L. D.) 507 



IV. Note on Lagoon-Phases and the Origin of Radiolarian Cherts 



(E. E. L. D.) 511 



(1) Introduction and Definition. 



(2) The Modiola Phases — Calcareous Lagoon-Phases — of Gower. 



(3) The Radiolarian Phase — Cherty Lagoon-Phase — of Gower. 



(4) Meaning of the Difference between the Modiola Phases and the 



Radiolarian Phase of Grower. 



(5) Topographical Position of Lagoon-Areas. 



(6) Earth-Movements accompanying Lagoon-Conditions. 



(7) Lagoon-Phases outside the South-Western Province. 



Y. Interpretation of the Lithological Sequence (E. E. L. D.) 532 



(1) Preliminary Remarks. 



(2) Variations in Depth and other Conditions of Deposition over 



Gower as a whole at Successive Times ; Conclusions ; Earth- 

 Movements. 



(3) Relations between the Different Districts of Gower at Suc- 



cessive Times ; Conclusions; Earth-Movements. 

 Summary of §§ III, IV, & V ; Acknowledgments. 

 VI. Notes on the Delimitation of the Upper from the Lower Avonian 



in the South-Western Province 542 



(1) From the Stratigraphical Standpoint (E. E. L. D.). 



(2) From the Faunal Standpoint (A. V.). 



VII. Faunal Lists (A. V.) 543 



VIII. Paloeontological Notes (A. V.) 553 



(A) Corals. 



(B) Brachiopods. 



IX. Summary of Palasontological Sections 565 



I. Introduction [E.E.L.D.& A. V.]. 



The object with which the Avonian rocks of Gower (figs. 1 & 2) 

 described in the present paper were examined was primarily the 

 comparison of their faunal sequence with that of Bristol and other 

 parts of the South-Western Province. In this connexion valuable 

 pioneer work on parts of the sequence had already been done bv 



2l2 



