Reports and Proceedings — Geological Society of London. 183 



in 1861, and Bonissent, in 1870, recorded the occurrence of con- 

 glomerates intercalated in the Pliyllads. Barrois, in 1884, gave a 

 list of the contained pebbles, amongst which was a " granite identical 

 with that of Chausey." Hebert, subsequently (1886) described this 

 conglomerate, also identifying the Chausey granite amongst the 

 pebbles, and he concluded that the conglomerate proved the existence 

 of granites " older than the Archeean," the term " Archaean " by this 

 writer being limited to the group called by us " Pebidian " or 

 "Uriconian." Bigot supports Hebert's contention, and carefully 

 distinguishes "the conglomerates of Granville, with pebbles of granite, 

 intercalated in the vertical Phyllads" from "the purple conglomerates, 

 almost hoi-izontal, forming the base of a series which the Ores 

 Armoricain contbrnaably overlies," that is to say, he makes the former 

 conglomerate Archaean, and the latter Cambrian. 



The conglomerate of Granville strongly suggests the Archgean. 

 conglomerate, which, at Charlton Hill near the Wrekin, contains 

 pebbles of a granite which is undistinguishable from a granite 

 exposed in the Wrekin and at Malvern : and, if Hebert and Bigot 

 are riglit in their reading of the Granville section, a granite of 

 Pre-Uriconian age is proved in both the British and French areas. 



Whether the Phyllads of Saint-L6 represent only the Pebidian 

 (Uriconian) of Britain, or also include the equivalent of the 

 Longrayndian, is at present an unsettled question. A small collection 

 of typical specimens from the Phyllads, sent some years ago by 

 Prof. Hebert to the present writer, would be considered thoroughly 

 typical of our Pebidian, and not at all like our Longmyndian. 



The rocks which unconformably overlie the Phyllads are con- 

 sidered by Dr. Bigot to represent the several horizons of our British 

 Cambrian. In the following table he indicates the parallelism which 

 he believes to subsist between the members of the older systems in 

 the two areas. 



Wales. 

 Areniff. 



Olenidian. 



Solva aud Menevian. 



Caerfai. 



Conglomerate. 



Pebidian. 



NORMANDIE. 



Gres armoricain. 



Gres feldspathiques. 

 Schistes verts et gres verts. 

 Schistes rouges et marbres. 

 Poudingues pourpres. 



Schistes de Saint-L6. 



s,:K!i=OI^TS j^n^zD i^-ie-OGiEZEZDin^rG-s. 



Geological Society of London. 



I. — Feb. 20, 1891. — Annual General Meeting. — Dr. A. Geikie, 

 F.R.S., President, in the Chair. 



The Secretaries read the Reports of the Council and of the Library 

 and Museum Committee for the year 1890. In the former the 

 Council once more congratulated the Fellows upon the continued 

 prosperity of the Society, as evinced by its increasing number and 

 by the satisfactory condition of its finances. 



