236 Reports and Proceedings — 



The Witwatersrand Series consists chiefly of sandstones, shales, 

 cherts, and quartzites, having an estimated thickness of 18,000 feet, 

 possibly formed in a hollow of the granite, and perhaps of marine 

 formation. 



The Klip-Eiver Series is formed of shales, flagstones, cherts, 

 and quartzites, with numerous interstratified traps, and is at least 

 18,000 feet thick. Near its base is the "Black Reef" and a 

 chalcedonite like that described by the author in connexion with 

 the Lydenberg district, which confirms his opinion that this area 

 is formed of part of the Megaliesberg formation. The base of the 

 series is generally conformable to the underlying rocks. The whole 

 of the lower half of the Megaliesberg formation is let down against 

 the north side of the granite south of Pretoria. 



The author divides the formation which he described in 1884 

 tinder the heading of High-Level Coalfields of South Africa into the 

 Kimberley Beds and the High Veldt Beds, The former thin out 

 eastward, and are overlapped by the latter, the estimated thickness 

 of which is 2300 feet. A volcanic rock overlies the Coal-formation. 

 Near the base of the formation is a bed of loose, calcareous, sandy 

 clay inclosing many waterworn pebbles, some of large size, derived 

 from the quartzites and "bankets" of the underlying formation. 

 The author is convinced that the region was under glacial influences 

 at some time during the long period which intervened between the 

 deposition of the Megaliesberg formation and of the coal-bearing 

 rocks of the High Veldt, which latter, he maintains, are certainly 

 Oolitic ; the latter contain Glossopteris (?) and Fishes, which he 

 considers to be nearly allied to Lepidotus valdensis, the latter being 

 from the Free State. 



The High- Veldt rocks are of fluviatile origin, and there appears 

 to have been continuity of fluviatile denudation from the close of the 

 Oolitic period until now. 



2. " On the Lower Limit of the Cambrian Series in N.W. Caer- 

 narvonshire." By Miss Catherine A. Raisin, B.Sc. Communicated 

 by Prof. T. G. Bonney, LL.D., F.R.S., V.P.G.S. 



In this paper the author examines the questions, whether the 

 Bangor beds should be included in the Cambrian series, and how the 

 strata associated with the southern felstone should be classed. The 

 lithological character of the rocks overlying the conglomerate at 

 Bangor is shown to be of little classificatory value, but the apparent 

 discordance between its strike and that of the beds beneath suggests 

 the inclusion of the latter in the pre-Cambrian series, as maintained 

 by Prof. Hughes and Prof. Bonney. 



The age of the northern beds must depend, however, to a great 

 extent upon the classification adopted for the Llyn Padarn rocks. 

 It has recently been proposed to regard the felstone of this district 

 as a lava-flow of Mid-Cambrian age, and the beds to the north as 

 lower strata included in the same great series. The author points 

 out as objections to this view : — (1) the enormous thickness of beds, 

 which in that case must be cut out by the supposed Arenig uncon- 

 formity at Caernarvon ; (2) the difficulty of assigning two lelsite 



