236 Beporfs and Proceedings — 



3. " A Comparative and Critical Revision of the Madreporaria of 

 the White Lias of the Middle and Western Counties of England, 

 and of those of the Conglomerate at the Base of the South- Wales 

 Lias." By Eobert F. Tomes, Esq., F.G.S. 



After referring to previous memoirs on the subject by MM. 

 Tawney, C. Moore, Tate, and Bristow, and to the conflicting con- 

 clusions arrived at by those geologists, the author insisted that the 

 Madreporaria are not necessarily contemporaneous with the beds in 

 which they are found imbedded. He took exception to some of 

 the identifications of these forms by Dr. Duncan, and suggested that 

 their nearest analogues are to be found in the St. Cassian beds. 



The few and imperfect corals of the White Lias of Warwickshire, 

 the author believes to have resemblances with the coral fauna of the 

 Sutton Stone on the one hand, and the St. Cassian beds on the other. 

 The Mollusca found in the same beds, however, are those of the 

 zone of Ammonites angulntus. 



While the Brocastle Conglomerate is, according to the author, a 

 local deposit with uncertain relations, the Sutton Stone is a much 

 more regular stratum, and is quite distinct from the conglomerate 

 which immediately overlies it, and which is seen at Southerndown. 

 He regarded the Sutton Stone as the equivalent of the White Lias, 

 and of RhEetic, not Liassic age. 



The revised list of corals found in the St. Cassian beds, the White 

 Lias, the Sutton Stone, and the Brocastle Conglomerate respectively, 

 shows, according to the author, that nearly all the White-Lias forms 

 occur at St. Cassian ; that a certain number of the Corals of those 

 two formations occur also in the Sutton Stone, but that none of 

 them occur at Brocastle ; and, furthermore, that the coral faunas of 

 Sutton are quite distinct. 



In conclusion, the author contested the views of the late Mr. C. 

 Moore concerning the existence of a series of conglomerates below 

 the base of the Sutton Stone, and insisted that the presence of a 

 Hettangian molluscan fauna in these beds and the White Lias is not 

 sutficient to counterbalance the evidence of Ehsetic affinities afforded 

 by the corals. The Brocastle Conglomerate, however, contains corals 

 with Liassic affinities. 



Detailed descriptions of the new sj)ecies of corals formed the con- 

 clusion of the paper. 



II.— April 2, 1884.— Prof. T. G. Bonney, D.Sc, F.R.S., President, 

 in the Chair. — The following communications were read : — 



1. " The Rocks of Guernsey." By the Rev. E. Hill, M.A., F.G.S. 

 With an Appendix on the Microscopic Structure of some of the 

 Rocks, by Prof. T. G. Bonney, D.Sc, F.R.S., Pres. G.S. 



The southern part of the island is a high plateau consisting en- 

 tirely of gneiss. This is very coarse, and the bedding is seldom well 

 marked. The bedding, when visible, coincides with the foliation, 

 and the author hopes that hereafter an order of succession may be 

 established. At Rocquaine Castle occur a few slaty beds intercalated 

 in the gneiss, the origin of which is somewhat difficult to understand. 



